Category: Class 8

Tamilnadu State Board New Syllabus Samacheer Kalvi 8th Tamil Book Solutions Guide Pdf Chapter 5.1 திருக்கேதாரம் Text Book Back Questions and Answers, Summary, Notes.

Tamilnadu Samacheer Kalvi 8th Tamil Solutions Chapter 5.1 திருக்கேதாரம்

கற்பவை கற்றபின்

Question 1.
தேவாரம் பாடிய மூவர் பற்றிய செய்திகளைத் திரட்டுக.
Answer:
திருஞானசம்பந்தர் :

• இயற்பெயர் – ஆளுடைய பிள்ளை
• பெற்றோர் – சிவபாத இருதயர், பகவதி அம்மையார்.
• ஊர் – சீர்காழி

தேவாரத்தின் முதல் நூலைப் பாடியவர். பன்னிரு திருமுறைகளில் ஒன்று, இரண்டு மற்றும் மூன்றாம் திருமுறை இவர் பாடியவை.

சிறு வயதில் மூன்று வயதுவரை பேசாதிருந்தார். உமையம்மை கொடுத்த ஞானப்பாலை உண்ணும்போது தோடுடைய செவியன் எனும் முதல் பாடலைப் பாடினார்.

திருநாவுக்கரசர் :

• இயற்பெயர் – மருள்நீக்கியார்
• சிறப்புப் பெயர்கள் – திருநாவுக்கரசர், வாகீசர், அப்பர், ஆளுடைய அரசு, தாண்டக வேந்தர், தருமசேனர்
• பெற்றோர் – புகழனார், மாதினியார்.
• தமக்கை – திலகவதியார்
• பிறந்த ஊர் – திருவாமூர்

இவர் பாடிய பாடல்கள் பன்னிரு திருமுறைகளுள் 4, 5, 6 ஆம் திருமுறைகளாகத் தொகுக்கப்பட்டுள்ளன.

சுந்தரர் :

• பிறந்த ஊர் – திருநாவலூர்
• பெற்றோர் – சடையனார், இசைஞானியார்.
• இயற்பெயர் – நம்பியாரூரர்
• சிறப்புப் பெயர்கள் – வன்தொண்டர், தம்பிரான் தோழர்.

இவருடைய பாடல்கள் ஏழாம் திருமுறையாகப் பன்னிரு திருமுறைகளுள் வைக்கப் பட்டுள்ளன.

பாடநூல் வினாக்கள்

சரியான விடையைத் தேர்ந்தெடுத்து எழுதுக.

Question 1.
காட்டிலிருந்து வந்த …………………… கரும்பைத் தின்றன.
அ) முகில்கள்
ஆ) முழவுகள்
இ) வேழங்கள்
ஈ) வேய்கள்
Answer:
இ) வேழங்கள்

Question 2.
‘கனகச்சுனை’ என்னும் சொல்லைப் பிரித்து எழுதக் கிடைப்பது ………………………..
அ) கனகச் + சுனை
ஆ) கனக + சுனை
இ) கனகம் + சுனை
ஈ) கனம் + சுனை
Answer:
இ) கனகம் + சுனை

Question 3.
முழவு + அதிர என்பதனைச் சேர்த்தெழுதக் கிடைக்கும் சொல் …………………….
அ) முழவுதிர
ஆ) முழவுதிரை
இ) முழவதிர
ஈ) முழவு அதிர
Answer:
இ) முழவதிர

குறுவினா

Question 1.
தமிழ் இசையோடு இணைந்து இசைக்கும் இசைக்கருவிகளாகச் சுந்தரர் கூறுவன யாவை?
Answer:
புல்லாங்குழல் மற்றும் முழவு ஆகியவற்றைத் தமிழ் இசையோடு இணைந்து இசைக்கும் இசைக் கருவிகளாகச் சுந்தரர் கூறுகின்றார்.

சிறு வினா

Question 1.
திருக்கேதாரத்தைச் சுந்தரர் எவ்வாறு வருணனை செய்கிறார்?
Answer:

• பண்ணோடு சேர்ந்த இனிய தமிழ்ப் பாடல்களைப் பாடும் போது, அதற்கு ஏற்றவாறு முதிர்ந்த மூங்கில்களால் ஆன புல்லாங்குழலும் முழவும் இணைந்து ஒலிக்கும்.
• கண்களுக்கு இனிய குளிர்ச்சிதரும் ஒளியை உடைய பொன் வண்ண நீர் நிலைகள் வைரங்களைப் போன்ற நீர்த் திவலைகளை வாரி இறைக்கும்.
• நிலத்தின் மீது நின்று கொண்டிருக்கும் மத யானைகள் மணிகளை வாரி வாரி வீசும். இவற்றால் இடையறாது தோன்றும் ‘கிண்’ என்னும் ஒலியானது இசையாக முழங்கும்.
• இத்தகைய சிறப்புகள் உடைய நகரம் திருக்கேதாரம் என்று சுந்தரர் வருணனை செய்கிறார்.

சிந்தனை வினா

Question 1.
விழாக்களின்போது இசைக்கருவிகளை இசைக்கும் வழக்கம் எவ்வாறு தோன்றியிருக்கும்
Answer:
என எழுதுக.
திருவிழாக் கூட்டத்தில் இரைச்சலைக் குறைக்கவும், திருவிழா நிகழ்வு நடக்கப் போகிறது என்பதை அறிவிக்கவும், இசைக்கு மயங்காத உயிர்கள் இல்லை. அந்த உயிர்களைப் படைத்த இறைவன் இசையை விரும்புவான். அதனால் விழாக்களின்போது இசைக்கருவிகள் இசைக்கும் வழக்கம் ஏற்பட்டிருக்கலாம்.

இசைக்கருவிகளை இசைக்கும் போது உணர்ச்சிப் பெருக்கும், பக்திப்பெருக்கும் ஏற்படுவதாலும் விழாக்களின் போது இசைக் கருவிகளை இசைக்கும் வழக்கம் தோன்றியிருக்கும்.

கூடுதல் வினாக்கள்

சரியான விடையைத் தேர்ந்தெடுத்து எழுதுக.

Question 1.
‘நம்பியாரூரர், தம்பிரான் தோழர்’ என்னும் சிறப்புப் பெயர்களால் அழைக்கப்பட்டவர்
அ) சுந்தரர்
ஆ) திருநாவுக்கரசர்
இ) மாணிக்கவாசகர்
ஈ) திருஞானசம்பந்தரர்
Answer:
அ) சுந்தரர்

Question 2.
தேவாரத்தைத் தொகுத்தவர் ……………………
அ) நம்பியாண்டார் நம்பி
ஆ) திருநாவுக்கரசர்
இ) சுந்தரர்
ஈ) திருஞானசம்பந்தர்
Answer:
அ) நம்பியாண்டார் நம்பி

Question 3.
பன்னிரு திருமுறைகளுள் ஏழாம் திருமுறையை இயற்றியவர் ……………………..
அ) திருஞானசம்பந்தர்
ஆ) சுந்த ரர்
இ) சேக்கிழார்
ஈ) நம்பியாண்டார் நம்பி
Answer:
ஆ) சுந்தரர்

Question 4.
‘திருக்கேதாரம்’ எனும் தலைப்பில் அமைந்த கவிதைப் பேழை பாடலை இயற்றியவர்
அ) நம்பியாண்டார் நம்பி
ஆ) சேக்கிழார்
இ) சுந்தரர்
ஈ) திருநாவுக்கரசர்
Answer:
இ) சுந்தரர்

Question 5.
பதிகம் என்பது ……………………. பாடல்களைக் கொண்டது.
அ) ஆறு
ஆ) நூறு
இ) பத்து
ஈ) இருபது
Answer:
இ) பத்து

Question 6.
பொன் வண்ண நிறமாக இருந்தவையாகச் சுந்தரர் குறிப்பிடுவன …………………….
அ) நீர்த்திவலைகள்
ஆ) நீர்நிலைகள்
இ) மணல்
ஈ) புல்லாங்குழல்
Answer:
ஆ) நீர்நிலைகள்

Question 7.
வைரங்களைப் போல இருந்தவையாகத் திருக்கேதாரம் குறிப்பிடுவன …………………
அ) புல்லாங்குழல்
ஆ) முழவு
இ) நீர்த்திவலைகள்
ஈ) நீர்நிலைகள்
Answer:
இ) நீர்த்திவலைகள்

குறுவினா

Question 1.
தேவாரம் பாடிய மூவர் யார்?
Answer:
திருஞானசம்பந்தர், திருநாவுக்கரசர், சுந்தரர்.

Question 2.
தேவாரம் பெயர்க்காரணம் கூறுக.
Answer:

• இறைவனுக்குச் சூட்டப்படும் மாலை (தே + ஆரம்)
• இனிய இசை பொருந்திய பாடல் (தே + வாரம்)

Question 3.
கண்ணுக்குக் குளிர்ச்சி தருபவை என்று சுந்தரர் எவற்றைக் குறிப்பிடுகிறார்?
Answer:
பொன் வண்ண நீர்நிலைகள் கண்களுக்கு இனிய குளிர்ச்சி தரும் என்று சுந்தரர் குறிப்பிடுகிறார்.

Question 4.
நீர் நிலைகள் மற்றும் நீர்த் திவலைகள் ஆகியவற்றிற்குக் கூறப்பட்ட உவமை யாது?
Answer:

• நீர் நிலைகள் – பொன்வண்ணம்
• நீர்த்திவலைகள் – வைரம்

Question 5.
மத யானைகளின் செயல்களாகச் சுந்தரர் குறிப்பிடுவன யாவை?
Answer:
நிலத்தின் மீது நின்று கொண்டிருக்கும் மத யானைகள் மணிகளை வாரி வாரி வீசும் என்று சுந்தரர் குறிப்பிடுகிறார்.

சிறுவினா

Question 1.
சுந்தரர் குறிப்பு வரைக.
Answer:
தேவாரம் பாடிய மூவரில் ஒருவர்.
சிறப்பு பெயர் : நம்பியாரூரர், தம்பிரான் தோழர்.
படைப்புகள் : பன்னிரு திருமுறைகளுள் ஏழாம் திருமுறை.

சொல்லும் பொருளும்

பண் – இசை
கனகச்சுனை – பொன் வண்ண நீர்நிலை
மதவேழங்கள் – மத யானைகள்
முரலும் – முழங்கும்
பழவெய் – முதிர்ந்த மூங்கில்

Tamilnadu State Board New Syllabus Samacheer Kalvi 8th Tamil Book Solutions Guide Pdf Chapter 2.6 திருக்குறள் Text Book Back Questions and Answers, Summary, Notes.

Tamilnadu Samacheer Kalvi 8th Tamil Solutions Chapter 2.6 திருக்குறள்

பாடநூல் வினாக்கள்

சரியான விடையைத் தேர்ந்தெடுத்து எழுதுக.

Question 1.
புகழாலும் பழியாலும் அறியப்படுவது ………………………….
அ) அடக்கமுடைமை
ஆ) நாணுடைமை
இ) நடுவுநிலைமை
ஈ) பொருளுடைமை
Answer:
இ) நடுவுநிலைமை

Question 2.
பயனில்லாத களர்நிலத்திற்கு ஒப்பானவர்கள் …………………….
அ) வலிமையற்றவர்
ஆ) கல்லாதவர்
இ) ஒழுக்கமற்றவர்
ஈ) அன்பில்லாதவர்
Answer:
ஆ) கல்லாதவர்

Question 3.
‘வல்லுருவம்’ என்னும் சொல்லைப் பிரித்து எழுதக் கிடைப்பது ……………………….
அ) வல் + உருவம்
ஆ) வன்மை + உருவம்
இ) வல்ல + உருவம்
ஈ) வ + உருவம்
Answer:
ஆ) வன்மை + உருவம்

Question 4.
நெடுமை + தேர் என்பதனைச் சேர்த்தெழுதக் கிடைக்கும் சொல் ……………………..
அ) நெடுதேர்
ஆ) நெடுத்தேர்
இ) நெடுந்தேர்
ஈ) நெடுமைதேர்
Answer:
இ) நெடுந்தேர்

Question 5.
‘வருமுன்னர்’ எனத் தொடங்கும் குறளில் பயின்று வந்துள்ள அணி ………………………
அ) தற்குறிப்பேற்ற அணி
ஆ) எடுத்துக்காட்டு உவமை அணி
இ) உவமை அணி
ஈ) உருவக அணி
Answer:
இ) உவமை அணி

குறுவினா

Question 1.
சான்றோர்க்கு அழகாவது எது?
Answer:
துலாக்கோல் போல நடுவுநிலைமையுடன் சரியாகச் செயல்படுவதே சான்றோர்க்கு அழகாகும்.

Question 2.
பழியின்றி வாழும் வழியாகத் திருக்குறள் கூறுவது யாது?
Answer:
தலைவன் முதலில் தன்குற்றத்தைக் கண்டு நீக்கி, அதன்பின் பிறருடைய குற்றத்தை ஆராய்ந்தால், அவனுக்கு எந்தப் பழியும் ஏற்படாது.

Question 3.
‘புலித்தோல் போர்த்திய பசு’ என்னும் உவமையால் திருக்குறள் விளக்கும் கருத்து யாது?
Answer:
மனத்தை அடக்கும் வல்லமை இல்லாதவர் மேற்கொண்ட தவக்கோலம், புலியின் தோலைப் போர்த்திக் கொண்ட பசு பயிரை மேய்ந்ததைப் போன்றது.

திருக்குறளைச் சீர் பிரித்து எழுதுக.

1. தக்கார் தகவிலரென்பது அவரவர் எச்சத்தால் காணப்படும்.
2. தொடங்கற்க எவ்வினையு மெள்ளற்க முற்று மிடங்கண்ட பின் அல்லது.

சீர்பிரித்தது

1. தக்கார் தகவிலர் என்பது அவரவர்
எச்சத்தால் காணப் படும்.

2. தொடங்கற்க எவ்வினையும் எள்ளற்க முற்றும்
இடங்கண்ட பின்அல் லது.

கோடிட்ட இடத்தை நிரப்புக.

1. வலியில் நிலைமையான் வல்லுருவம் ……………………….
புலியின்தோல் ……………………. மேய்ந் தற்று.

2. விலங்கொடு ………………….. அனையர் ……………………….
கற்றாரோடு ஏனை யவர்.
Answer:
1. பெற்றம், போர்த்து
2. மக்கள், இலங்குநூல்

சீர்களை முறைப்படுத்தி எழுதுக.

யாழ்கோடு அன்ன கொளல் கணைகொடிது
வினைபடு பாலால் செவ்விதுஆங்கு.

முறைப்படுத்தியது
கணைகொடிது யாழ்கோடு செவ்விது ஆங்கு அன்ன
வினைபடு பாலால் கொளல்.

படங்களுக்குப் பொருத்தமான திருக்குறள்களை எழுதுக.

1. வலியில் நிலைமையான் வல்லுருவம் பெற்றம்
புலியின் தோல் போர்த்துமேய்ந் தற்று.

2. கடல்ஓடா கால்வல் நெடுந்தேர் கடல் ஓடும்
நாவாயும் ஓடா நிலத்து.

கூடுதல் வினாக்கள்

சரியான விடையைத் தேர்ந்தெடுத்து எழுதுக.

Question 1.
எல்லா மக்களுக்கும் பொருந்தும் அறக்கருத்துகளைக் கொண்ட நூல் ……………………
அ) பரிபாடல்
ஆ) குறுந்தொகை
இ) திருக்குறள்
ஈ) நற்றிணை
Answer:
இ) திருக்குறள்

Question 2.
திருக்குறளின் பெருமையை விளக்கும் நூல் …………………..
அ) ஆத்திசூடி
ஆ) புறநானூறு
இ) கலித்தொகை
ஈ) திருவள்ளுவமாலை
Answer:
ஈ) திருவள்ளுவமாலை

Question 3.
நடுவுநிலைமையுடன் செயல்படுவதே ………………. அழகாகும்.
அ) கயவர்க்கு
ஆ) சான்றோர்க்கு
இ) கல்லாதார்க்கு
ஈ) மூடர்க்கு
Answer:
ஆ) சான்றோர்க்கு

Question 4.
‘வலியில்’ எனத் தொடங்கும் குறளில் பயின்று வந்துள்ள அணி ……………………
அ) உவமையணி
ஆ) எடுத்துக்காட்டு உவமையணி
இ) உருவக அணி
ஈ) இல்பொருள் உவமை அணி
Answer:
ஈ) இல்பொருள் உவமை அணி

Question 5.
மக்களின் பண்புகளை அவரவர் தோற்றத்தால் அல்லாமல் …………………………… வகையால் உணர்ந்து கொள்ள வேண்டும்.
அ) அன்பு
ஆ) செயல்
இ) நட்பு
ஈ) பாசம்
Answer:
ஆ) செயல்

Question 6.
கற்றவர்க்கும் கல்லாதவர்க்கும் இடையே உள்ள வேறுபாடு மக்களுக்கும் ……………………… இடையே உள்ள வேறுபாட்டிற்கு இணையானது.
அ) பறவைகளுக்கும்
ஆ) கயவர்களுக்கும்
இ) விலங்குகளுக்கும்
ஈ) மரங்களுக்கும்
Answer:
இ) விலங்குகளுக்கும்

Question 7.
……………. வருமுன்னே சிந்தித்து நம்மைக் காத்துக் கொள்ள வேண்டும்.
அ) வலி
ஆ) பழி
இ) சளி
ஈ) உளி
Answer:
ஆ) பழி

Question 8.
பழிவருமுன்னே காக்காதவர் வாழ்க்கை, நெருப்பின் அருகில் வைக்கப்பட்ட …………………….. போல அழிந்துவிடும்.
அ) வைக்கோல்போர்
ஆ) பஞ்சு
இ) தாள்
ஈ) மரம்
Answer:
அ) வைக்கோல்போர்

Question 9.
‘கடல் ஓடா’ எனத் தொடங்கும் குறளில் பயின்று வந்துள்ள அணி ………………………..
அ) பிறிதுமொழிதல் அணி
ஆ) தற்குறிப்பேற்ற அணி
இ) உருவக அணி
ஈ) உவமையணி
Answer:
அ) பிறிது மொழிதல் அணி

Question 10.
முதற்பாவலர் என்று அழைக்கப்படுபவர் ……………………
அ) நக்கீரர்
ஆ) கம்ப ர்
இ) வள்ளுவர்
ஈ) கபிலர்
Answer:
இ) வள்ளுவர்

Question 11.
திருவள்ளுவர் ……………………… ஆண்டுகளுக்கு முற்பட்டவர் என்பர்.
அ) 1000
ஆ) 500
இ) 1500
ஈ) 2000
Answer:
ஈ) 2000

Question 12.
………………………. உலகின் பல்வேறு மொழிகளில் மொழி பெயர்க்கப்பட்ட சிறந்த நூல் ஆகும்.
அ) பெரிய புராணம்
ஆ) திருக்குறள்
இ) தேவாரம்
ஈ) நற்றிணை
Answer:
ஆ) திருக்குறள்

Question 13.
திருக்குறள் ……………….. பகுப்புக் கொண்டது.
அ) ஐம்பால்
ஆ) எண்பால்
இ) முப்பால்
ஈ) ஒன்பால்
Answer:
இ) முப்பால்

Question 14.
அறத்துப்பால் ……………………….. இயல்களைக் கொண்டது.
அ) இரண்டு
ஆ) மூன்று
இ) நான்கு
ஈ) ஐந்து
Answer:
இ) நான்கு

Question 15.
பொருட்பால் ………………. இயல்களைக் கொண்டது.
அ) இரண்டு
ஆ) மூன்று
இ) நான்கு
ஈ) ஐந்து
Answer:
ஆ) மூன்று

Question 16.
இன்பத்துப்பால் ………………………. இயல்களைக் கொண்டது.
அ) இரண்டு
ஆ) மூன்று
இ) நான்கு
ஈ) ஐந்து
Answer:
அ) இரண்டு

Question 17.
‘அவரவர்’ என்னும் சொல்லைப் பிரித்து எழுதக் கிடைப்பது ……………………….
அ) அவர + வர்
ஆ) அவர + அவர்
இ) அ + அவர்
ஈ) அவர் + அவர்
Answer:
ஈ) அவர் + அவர்

Question 18.
‘தகவிலர்’ என்னும் சொல்லைப் பிரித்து எழுதக் கிடைப்பது ……………………..
அ) தக + விலர்
ஆ) தக + இலர்
இ) தகவு + இலர்
ஈ) தகவு + பலர்
Answer:
இ) தகவு + இலர்

Question 19.
‘நிலைமையான்’ என்னும் சொல்லைப் பிரித்து எழுதக் கிடைப்பது …………………….
அ) நிலை + யான்
ஆ) நிலைமை + ஆன்
இ) நிலைமை + யான்
ஈ) நிலைமை + ஏன்
Answer:
ஆ) நிலைமை + ஆன்

Question 20.
‘மேய்ந்தற்று’ என்னும் சொல்லைப் பிரித்து எழுதக் கிடைப்பது ……………………..
அ) மேய் + அற்று
ஆ) மேய்ந் + தற்று
இ) மேயும் + அற்று
ஈ) மேய்ந்து + அற்று
Answer:
ஈ) மேய்ந்து+அற்று

Question 21.
‘பாலால்’ என்னும் சொல்லைப் பிரித்து எழுதக் கிடைப்பது …………………..
அ) பா + ஆல்
ஆ) பால் + ஆல்
இ) பாலு + ஆல்
ஈ) பா + லால்
Answer:
ஆ) பால் + ஆல்

Question 22.
‘கல்லாதவர்’ என்னும் சொல்லைப் பிரித்து எழுதக் கிடைப்பது …………………..
அ) க + அவர்
ஆ) கல் + லாதவர்
இ) கல்லாது + அவர்
ஈ) கல்லா + அவர்
Answer:
இ) கல்லாது + அவர்

Question 23.
‘விலங்கொடு’ என்னும் சொல்லைப் பிரித்து எழுதக் கிடைப்பது …………………….
அ) விலங் + கொடு
ஆ) விலங்கு + ஒடு
இ) விலங்க + கொடு
ஈ) விலங்கு + ஓடு
Answer:
ஆ) விலங்கு + ஒடு

Question 24.
‘கற்றாரோடு’ என்னும் சொல்லைப் பிரித்து எழுதக் கிடைப்பது ……………………….
அ) கற்றார் + ஓடு
ஆ) கற்றார் + ஒடு
இ) கற்றா + ரோடு
ஈ) கற் + றாரோடு
Answer:
அ) கற்றார் + ஓடு

Question 25.
‘வைத்து + ஊறு’ என்பதனைச் சேர்த்தெழுதக் கிடைக்கும் சொல் ………………
அ) வைத்து ஊறு
ஆ) வைத்தாறு
இ) வைத்தூறு
ஈ) வைத்துறு
Answer:
இ) வைத்தூறு

Question 26.
‘இடம் + கண்ட’ என்பதனைச் சேர்த்தெழுதக் கிடைக்கும் சொல் ………………….
அ) இடம்கண்ட
ஆ) இடகண்ட
இ) இடத்தைக்கண்ட
ஈ) இடங்கண்ட
Answer:
ஈ) இடங்கண்ட

Question 27.
‘நாவாய் + உம்’ என்பதனைச் சேர்த்தெழுதக் கிடைக்கும் சொல் ………………
அ) நாவாய்உம்
ஆ) நாவாயும்
இ) நாவாஉம்
ஈ) நாவாஊம்
Answer:
ஆ) நாவாயும்

அணிகள்

1. இல்பொருள் உவமை அணி
அணி விளக்கம் :
உலகத்தில் இல்லாத பொருளை உவமையாக்கிக் கூறுவது இல்பொருள் உவமை அணி ஆகும்.

எ.கா:
‘வலியில் நிலைமையான் வல்லுருவம் பெற்றம்
புலியின்தோல் போர்த்துமேய்ந் தற்று.’
அணிப்பொருத்தம் : பசுவானது புலியின்தோலைப் போர்த்திக் கொண்டு பயிரை மேய்ந்தல் உலகில் இல்லாத செயலாகும். எனவே அதனை உவமையாக்கிக் கூறியுள்ளமையால், இது இல்பொருள் உவமை அணி ஆயிற்று.

2. உவமை அணி :

அணி விளக்கம் :
உவமை, பொருள், உவம உருபு ஆகியவை வெளிப்படையாக தோன்றுமாறு அமைவது உவமை அணி ஆகும்.

எ.கா – 1:
சமன்செய்து சீர்தூக்கும் கோல்போல் அமைந்து ஒருபால்
கோடாமை சான்றோர்க்கு அணி.

அணிப்பொருத்தம் :
இப்பாடலில் துலாக்கோலை உவமையாகக் கூறி, சான்றோர்களின் நடுவுநிலைமையை உவமிக்கப்படும் பொருளாக்கி, போல என்ற உவம உருபு வெளிப்படையாகத் தோன்றுமாறு அமைக்கப்பட்டுள்ளதால் அது உவமை அணி ஆயிற்று.

எ.கா – 2:
வருமுன்னர்க் காவாதான் வாழ்க்கை எரிமுன்னர்
வைத்தூறு போலக் கெடும்.

அணிப்பொருத்தம் :
நெருப்பின் அருகில் வைக்கப்பட்ட வைக்கோல் போரை உவமையாகக் கூறி, பழிவருமுன்னே சிந்தித்து செயல்படுபவன் வாழ்க்கை என்பதை உவமிக்கப்படும் பொருளாக்கி, போல என்ற உவம உருபு பெற்று, வெளிப்படையாய் அமைந்துள்ளதால் இது உவமை அணி ஆயிற்று.

3. பிறிது மொழிதல் அணி :

அணி விளக்கம் :
உவமையை மட்டும் கூறிப் பொருளினைப் பெற வைப்பது பிறிது மொழிதல் அணி.

எ.கா:
கடல் ஓடா கால்வல் நெடுந்தேர் கடல் ஓடும்
நாவாயும் ஓடா நிலத்து.

அணிப்பொருத்தம் :
அவரவர் தமக்குரிய இடங்களிலேயே சிறப்பாகச் செயல்பட முடியும் என்பதே புலவர் கூற விரும்பிய கருத்து. ஆனால் அதனைக் கூறாமல் பெரிய தேர் கடலில் ஓடாது. கடலில் ஓடும் கப்பல் தரையில் ஓடாது என உவமையாக வேறொன்றைக் கூறியுள்ளார். ஆகவே இது பிறிது மொழிதல் அணி ஆயிற்று.

Students can Download Maths Chapter 1 Numbers Ex 1.4 Questions and Answers, Notes Pdf, Samacheer Kalvi 8th Maths Book Solutions Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus and score more marks in your examinations.

Tamilnadu Samacheer Kalvi 8th Maths Solutions Term 3 Chapter 1 Numbers Ex 1.4

Samacheer Kalvi 8th Maths Book Solutions Exercise 1.4 Question 1.
Fill in the blanks:
(i) (-1 )^{even integer} is…………
(ii) For a ≠ 0, a° is……….
(iii) 4^-3 × 5^-3 =…………
(iv) (-2)⁷ =………….
(v) \((-\frac{1}{3})^{-5}\) =…………
Solution:
(i) 1
(ii) 1
(iii) 20^-3
(iv) \(\frac{-1}{128}\)
(v) -243

Samacheer Kalvi 8th Maths Solutions Term 3 Pdf Question 2.
Say True or False:
(i) If 8^x = \(\frac{1}{64}\), the value of x is -2
(ii) The simplified form of (256)^-1/4 is \(\frac{1}{4}\)
(iii) The standard form of 2 x 10^-4 is 0.0002.
(iv) The scientific form of 123.456 is 1.23456 x 10^-2.
(v) The multiplicative inverse of (3)^-7 is 3⁷.
Solution:
(i) True
(ii) True
(iii) True
(iv) False
(v) True

8th Maths Exercise 1.4 Samacheer Kalvi Question 3.
Evaluate:
(i) \(\left(\frac{1}{2}\right)^{3}\)
Solution:
\(\left(\frac{1}{2}\right)^{3}=\frac{1^{3}}{2^{3}}=\frac{1}{2 \times 2 \times 2}=\frac{1}{8}\)

(ii) \(\left(\frac{1}{2}\right)^{-5}\)
Solution:
\(\left(\frac{1}{2}\right)^{-5}=\frac{1^{-5}}{2^{-5}}=\frac{1}{2^{-5}}=2^{5}\) = 2 × 2 × 2 × 2 × 2 = 32

(iii) (-3)^-3
Solution:
(-3)^-3 = \(\frac{1}{(-3)^{3}}=\frac{1}{-3 \times-3 \times-3}=\frac{1}{-27}=\frac{-1}{27}\)

(iv) (-3)⁴
Solution:
(-3)⁴ = -3 × -3 × -3 × -3 = 81

(v) \(\left(\frac{-5}{6}\right)^{-3}\)
Solution:
\(\left(\frac{-5}{6}\right)^{-3}=\frac{(-5)^{-3}}{6^{-3}}=\frac{6^{3}}{(-5)^{3}}=\frac{6 \times 6 \times 6}{-5 \times-5 \times-5}=-\frac{216}{125}\)

(vi) \(\left( { 2 }^{ -5 }\div { 2 }^{ 7 } \right) \times { 2 }^{ -2 }\)
Solution:
\(\left( { 2 }^{ -5 }\div { 2 }^{ 7 } \right) \times { 2 }^{ -2 }\) = \(\left( { 2 }^{ -5-7 }\right)\times { 2 }^{ -2 }\)
\(2^{-12} \times 2^{-2}=2^{-12+(-2)}=2^{-14}\)

(vii) \(\left( { 2 }^{ -1 }\times { 3 }^{ -1 } \right) \div 6^{ -2 }\)
Solution:
\(\left( { 2 }^{ -1 }\times { 3 }^{ -1 } \right) \div 6^{ -2 }\) = \((2 \times { 3})^{ -1 } \div 6^{ -2 }\)
= \((6)^{-1} \div 6^{-2}=6^{(-1)-(-2)}=6^{1}=6\)

(viii) \(\left(-\frac{1}{3}\right)^{-2}\)
Solution:
\(\left(-\frac{1}{3}\right)^{-2}=\left(-\frac{3}{1}\right)^{2}=\frac{(-3)^{2}}{1^{2}}=\frac{-3 \times-3}{1}\) = 9

Samacheer Kalvi 8th Maths Book Solutions Question 4.
Evaluate:
(i) \(\left(\frac{2}{5}\right)^{4} \times\left(\frac{2}{5}\right)^{2}\)
Solution:
\(\left(\frac{2}{5}\right)^{4} \times\left(\frac{2}{5}\right)^{2}\) = \(\left(\frac{2}{5}\right)^{4+2}=\left(\frac{2}{5}\right)^{6}\)

(ii) \(\left(\frac{4}{5}\right)^{-2} \times\left(\frac{4}{5}\right)^{-3}\)
Solution:
\(\left(\frac{4}{5}\right)^{-2} \times\left(\frac{4}{5}\right)^{-3}\) = \(\left(\frac{4}{5}\right)^{-2+(-3)}=\left(\frac{4}{5}\right)^{-5}\)

(iii) \(\left(\frac{1}{2}\right)^{-3} \times\left(\frac{1}{2}\right)^{7}\)
\(\left(\frac{1}{2}\right)^{-3} \times\left(\frac{1}{2}\right)^{7}\) = \(\left(\frac{1}{2}\right)^{-3+7}=\left(\frac{1}{2}\right)^{4}\)

Samacheer Kalvi Guru 8th Maths Question 5.
Evaluate:
(i) \(\left( { 5 }^{ 0 }+{ 6 }^{ -1 } \right) \times { 3 }^{ 3 }\)
Solution:

(ii) \(\left( 2^{ -1 }\times { 3 }^{ -1 } \right) \div { 6 }^{ -1 }\)
Solution:
\(\left( 2^{ -1 }\times { 3 }^{ -1 } \right) \div { 6 }^{ -1 }\) = \((2 \times 3)^{-1} \div 6^{-1}=6^{-1}+6^{-1}=6^{-1-(-1)}=6^{0}\) = 1

(iii) \(\left( 3^{ -1 }+{ 4 }^{ -2 }+{ 5 }^{ -3 } \right) ^{ 0 }\)
Solution:
\(\left( 3^{ -1 }+{ 4 }^{ -2 }+{ 5 }^{ -3 } \right) ^{ 0 }\) = 1 [ ∴ a° = 1 where a ≠ 0]

Samacheer Kalvi Guru 8th Maths Book Solutions Question 6.
Simplify
(i) \(\left(3^{2}\right)^{3} \times\left(2 \times 3^{5}\right)^{-2} \times(18)^{2}\)
Solution:

Samacheer Kalvi.Guru 8th Maths Question 7.
Solve for x.
(i) \(\frac{10^{x}}{10^{-3}}=10^{9}\)
Solution:
\(\frac{10^{x}}{10^{-3}}=10^{9}\)
\({10^{x+3}}=10^{9}\)
Equating the powers of same base 10
x + 3 = 9
x + 3 – 3 = 9 – 3
x = 6

(ii) \(\frac{2^{2x-1}}{2^{x+2}}\) = 4
Solution:
\(2^{2x-1-1(x+2)}\) = 2²
\(2^{2x-1-x-2}\) = 2²
\(2^{x-3}\) = 2²
Equating the powers of the same base 2.
x – 3 = 2
x – 3 + 3 = 2 + 3
x = 5

(iii) \(\frac{5^{5} \times 5^{-4} \times 5^{x}}{5^{12}}=5^{-5}\)
Solution:
\(\frac{5^{5} \times 5^{-4} \times 5^{x}}{5^{12}}=5^{-5}\) = \(5^{-5} \Rightarrow \frac{5^{5-4+x}}{5^{12}}=5^{-5}\)
\(\Rightarrow \frac{5^{1+x}}{5^{12}}\) = 5^-5
⇒ \(5^{1+x-12}\) = 5^-5
⇒ \(5^{x-11}\) = 5^-5
Equating the powers of same base 5.
x – 11 = -5
x – 11 + 11 = -5 + 11
x = 6

Samacheer Kalvi Guru 8th Maths Guide Question 8.
Expand using exponents:
(i) 6054.321
(ii) 897.14
Solution:

Samacheerkalvi.Guru 8th Maths Question 9.
Find the number is standard form:
(i) 8 x 10⁴ + 7 x 10³ + 6 x 10² + 5 x 10¹+ 2 x 1 + 4 x 10^-2 + 7 x 10^-4
Solution:
8 x 10⁴ + 7 x 10³ + 6 x 10² + 5 x 10¹ + 2 x 1 + 4 x 10^-2 + 7 x 10^-4
= 8 x 10000 + 7 x 1000 + 6 x 100 + 5 x 10 + 2 x 1 + 4 x \(\frac{1}{100}\) + 7 x \(\frac{1}{10000}\)
= 80000 + 7000 + 600 + 50 + 2 + \(\frac{4}{100}\) + \(\frac{7}{10000}\)
= 87652.0407

(ii) 5 x 10³ + 5 x 10¹ + 5 x 10^-1 + 5 x 10^-3
Solution:
5 x 10³ + 5 x 10¹ + 5 x 10^-1 + 5 x 10^-3
= 5 x 1000 + 5 x 10 + 5 x \(\frac{1}{10}\) + 5 x \(\frac{1}{1000}\)
= 5000 + 50 + \(\frac{5}{10}\) + \(\frac{5}{1000}\) = 5050.505

8th Maths Exercise 1.4 Question 10.
The radius of a hydrogen atom is 2.5 x 10 11 m. Express this number in standard notation.
Solution:
Radius of a hydrogen atom = 2.5 x 10¹¹ m
= 2.5 x \(\frac{1}{10^{11}}\) m = \(\frac{2.5}{10^{11}}\) m = 0.000000000025 m

Samacheer Kalvi Guru 8 Maths Question 11.
Write each number in scientific notation:
(i) 467800000000
(ii) 0.000001972
Solution:

Samacheer Kalvi 8th Maths Solutions Question 12.
Write in scientific notation:
(i) Earth’s volume is about 1,083,000,000,000 cubic kilometers.
Solution:

Earth’s volume = 1.083 x 10¹² cubic kilometers.

(ii) If you fill a bucket with dirt, the portion of the whole Earth that is in the bucket will be 0.0000000000000000000000016 kg.
Solution:
Portion of earth in the bucket =  kg = 1.6 x 10^-24 kg.

Objective Type Questions

Samacheer Kalvi 8th Maths Book Solution Question 13.
By what number should (-4)^-1 be multiplied so that the product becomes 10^-1?
(a) \(\frac{2}{3}\)
(b) \(\frac{-2}{5}\)
(c) \(\frac{5}{2}\)
(d) \(\frac{-5}{2}\)
Solution:
(b) \(\frac{-2}{5}\)
Hint:

Question 14.
0.0000000002020 in scientific form is
(a) 2.02 x 10⁹
(b) 2.02 x 10^-9
(c) 2.02 x 10^-8
(d) 2.02 x 10^-10
Solution:
(d) 2.02 x 10^-10
Hint:

Question 15.
(-2)^-3 x (-2)^-2 is
(a) \(\frac{-1}{32}\)
(b) \(\frac{1}{32}\)
(c) 32
(d) -32
Solution:
(a) \(\frac{-1}{32}\)

Question 16.
Which is not correct?
(a) \(\left(\frac{-1}{4}\right)^{2}\) = 4^-2
(b) \(\left(\frac{-1}{4}\right)^{2}\) = \(\left(\frac{1}{2}\right)^{4}\)
(c) \(\left(\frac{-1}{4}\right)^{2}\) = 16^-1
(d) \(-\left(\frac{1}{4}\right)^{2}\) = 16^-1
Solution:
(d) \(-\left(\frac{1}{4}\right)^{2}\) = 16^-1
Hint:
\((-2)-3 x(-2)-2=(-2)-3-2=(-2)-5\left(-\frac{1}{2}\right) 5=-\frac{1}{32}\)

Question 17.
If \(\left(\frac{p}{q}\right)^{1-3 x}=\left(\frac{q}{p}\right)^{\frac{1}{2}}\), then x is
(a) 4^-1
(b) 3^-1
(c) 2^-1
(d) 1^-1
Solution:
(c) 2^-1
Hint:

Students can Download Social Science Civics Term 3 Chapter 1 Public and Private Sectors Questions and Answers, Notes Pdf, Samacheer Kalvi 8th Social Science Book Solutions Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus and score more marks in your examinations.

Tamilnadu Samacheer Kalvi 8th Social Science Economics Solutions Term 3 Chapter 1 Public and Private Sectors

Samacheer Kalvi 8th Social Science Economics Public and Private Sectors Textual Evaluation

I. Choose the best answer:

Public Sector Is On Dash Motive Question 1.
The public sector in India owes its origin in the ………… Industrial policy resolution of the Government of India.
(a) 1957
(b) 1958
(c) 1966
(d) 1956
Answer:
(d) 1956

The Private Sector Is On Dash Motive Question 2.
Mixed economy is the mixture of merits of both …………
(a) Capitalism
(b) Socialism
(c) a & b are correct
(d) A & B are incorrect
Answer:
(c) a & b are correct

The Private Sector Is On Motive Question 3.
………… is governed by a company law and controlled by the Government as principal major share holders.
(a) Private Sector
(b) Joint Sector
(c) Public Sector
(d) None of these
Answer:
(b) Joint Sector

Private Sector Is On Dash Motive Question 4.
Steel Authority of India Ltd (SAIL) is a ………… Industry.
(a) Miniratna Industry
(b) Maharatna Industry
(c) Navaratna Industry
(d) None of these
Answer:
(b) Maharatna Industry

Public Sector Is On Motive Question 5.
Public sector is on ………… motive.
(a) Profit Motive
(b) Service Motive
(c) Speculative Motive
(d) None of these
Answer:
(b) Service

II. Fill in the Blanks:

1. The ………… and are allotted their respective roles in promoting the economic welfare of all sections of the community.
2. The private sector is on ………… motive.
3. ………… is the process of social and economic development in a society.
4. The main function of private sector is to create ………… and …………
5. The government is committed to strengthening ………… and co-operation among the citizens.

Answer:

1. Public sector and Private sector
2. profit
3. Socio Economic Development
4. Innovation and Moderisation
5. understanding

III. Match the following:

1. Think Tank – Primary Sector
2. Agriculture – Gross Domestic Product
3. Industries – NITI Aayog
4. GDP – Navaratna Industry
5. BHEL – Secondary Sector

Answer:

1. Think Tank – NITI Aayog
2. Agriculture – Primary Sector
3. Industries – Secondary Sector
4. GDP – Gross Domestic Product
5. BHEL – Navaratna Industry

IV. Which is the Odd one:

Public Sector Is An Dash Motive Question 1.
Which one of the following is not the indicator of the Socio Economic Development.
(a) Black Money
(b) Life Expectancy
(c) Gross Domestic Product (GDP)
(d) Employment
Answer:
(a) Black Money

V. Which of the following is a correct answer:

Question 1.
(i) The Industries which would be exclusively owned by the state are referred to as Schedule-A
(ii) The industries in which the private sector could supplement the efforts of the state sector, with the state taking the sole responsibility for starting new units which are specific in Schedule-B.
(iii) The remaining industries which were in the private sector are not mentioned in Schedule,

(a) All are Correct
(b) (i) and (iii) are correct
(c) (i) and (ii) are correct
(d) None of these
Answer:
(c) (i) and (ii) are correct

VI. Short Answer:

Question 1.
Write short note on public sectors.
Answer:

1. The sector, which is engaged in the activities of providing government goods and services to the general public is known as Public Sector.
2. The enterprises, agencies, and bodies are fully owned, controlled and run by the government whether it is central government, state government or a local government.

Question 2.
What does the society want?
Answer:
The society wants rapid industrialization of the economy as the main key to economic development, improving living standards and
economic sovereignty.

Question 3.
Write the objectives of Public sector.
Answer:
The objectives of Public Sector:

1. To promote rapid economic development through creation and expansion of infrastructure
2. To generate financial resources for development
3. To promote redistribution of income and wealth
4. To create employment opportunities

Question 4.
What are the three organs of public sectors?
Answer:
The three organs of public sector are:

1. Administration by a Government Department
2. The Joint sector companies
3. Public Corporation

Question 5.
Name some indicators that measure socioeconomic development.
Answer:
Socioeconomic development is measured with indicators, such as GDP, life expectancy, literacy and levels of employment.

Question 6.
Write short note on Private sector.
Answer:

1. The segment of a national economy that is owned, controlled and managed by private individuals or enterprises is known as Private sector.
2. The private sector companies are divided on the basis of sizes.
3. They can be created in two ways, i.e. either by the formation of a new enterprise or by the privatization of any public sector enterprise.

Question 7.
Name any three Maratha Industries.
Answer:

1. National Thermal Power Corporation (NTPC)
2. Oil and Natural Gas Commission (ONGC)
3. Steel Authority of India Limited (SAIL)

Question 8.
Name any three Major Private Sector industries.
Answer:

1. Infernos
2. Aditya Birla Company
3. Tata Group of Companies

VII. Brief Answer:

Question 1.
Explain the organs of public sector.
Answer:
1. Administration by a Government Department:

• It is very common almost in all countries.
• Example: Post and Telegraph, Railways, Port Trust, Irrigation Projects on India etc.,

2. The Joint sector companies:

• It is governed by a company law and controlled by the Government as principal major share holders.
• Example – Indian Oil Personas pvt ltd, Indian Oil Sky tanking Limited. Ratting Gas and Power Private Limited Indian Synthetic Rubber Limited.

3. Public Corporation:

• This type of organization is the establishment of public corporation by the state of the parliament of legislature.
• Example – LIC, Air India, The Reserve bank of India, Electricity Board.

Question 2.
Write briefly explain the history of public sector.
Answer:
History of Public Sector:

1. When India achieved independence in 1947, it was primarily an agricultural country with a weak industrial base. It is established for their own economic interest and rule the subcontinent with brute force.
2. The first Industrial Policy Resolution announced in 1948 laid down broad contours of the strategy of industrial development.
3. The Planning Commission was formed in March 1950 and the Industrial Act was enacted in 1951.
4. Pandit Jawaharlal Nehru believed that the establishment of basic and heavy industry was fundamental to the development and modernisation of the Indian economy.
5. His vision was carried forward by Dr. V. Krishnamurthy and the Indian statistician Mahalanobis.
6. The 1991 industrial policy allowed greater freedom to the private sector and foreign direct investment was invited from business houses outside india.
7. Thus, multinational corporations gained entry into the Indian economy.
8. Thus, we have public sector units, private sector enterprises and multinational Coexisting in Indian economy.

Question 3.
Explain any five measured indicators of socioeconomic development.
Answer:
1. Gross Domestic Product (GDP):

• GDP supports in developing socio – Economic Development.
• The proportion of GDP by the industrial sector both private and public sector has been increased.
• It results increasing government funds and increase public spending.

2. Life Expectancy:

• The life expectancy in India is 65.80 years for men and 68.33 years for women.
• Government provides high degree of health measures through National Health Production Scheme and serves poor and vulnerable families.

3. Literacy:

• Sarva Siksha Abhiyan(SSA) implemented for making free and Compulsory Education to the children of 6-14 years with life skills.
• The Government also introduced RMSA, Smart class, Fleming, free computer skill classes and Digital India for increasing the level of quality in education.

4. Employment:

• A growing number of people moved urban areas in search of employment.
• Hence Government started the Smart city with many facilities to encourage people to take up employment in these places.
• The Government encourages private sectors to start an industry in backward areas by providing tax benefit electricity at a lower tariff, etc.,
• Provision of House, Clean Drinking Water and Sanitation – Government sector provides housing facilities, clean drinking water facilities and sanitary facilities under clean India Planning.

Question 4.
What are the importance of public sector?
Answer:
Public sector plays a major role in the development of any economy. It has following importance:
1. Public Sector and Capital Formation:

• The role of public sector in collecting, saving and investing them during the planning period has been very important.

2. Economic Development:

• Economic development mainly depends upon industrial development.
• Heavy and basic industries like Iron and steel, shipping, mining, etc. are required for supplying raw materials to small industries.

3. Balanced Regional Development:

• Public enterprises have developed the backward areas thereby bringing about complete transformation in the socio-economic life of the people in these regions.

4. Employment generation:

• Public sector has created millions of jobs to tackle the unemployment problem in the country.
• The number of persons employed during the year 2011 was 150 lake.

5. Export Promotion and Foreign Exchange Earnings:

• Some public enterprises have done much to promote India’s export.
• The State Trading Corporation (STC). The Minerals and Metals Trading Corporation (MMTC) have done very well in export promotion.

6. Protection to Sick Industries:

• Public sector takes over the sick industries and prevent many people from getting unemployed.
• It also prevents unnecessary locking of capital, land, building, machinery,etc.

7. Import Substitution:

• Some public sector enterprises were started specifically to save foreign exchange.
• The ONGC, the Indian Oil Corporation Ltd., the Bharat Electronics Ltd., etc., have saved foreign exchange by way of import substitution.

Question 5.
Write the Differences between public and private sector.
Answer:
Public Sector:

1. Ownership of industries is with government
2. Public Revenue Depends upon levy of taxes, on income and commodities and services
3. Public sector ensures the proper wage
4. It does not allow to concentrate huge wealth in few hands or rich people Eg – NLC, SAIL, BSNL.
5. No tax evasion
6. It is service oriented
7. Reservations are implemented. Priority is given to the socially backward people

Private Sector:

1. Ownership of industries is with private individuals
2. Issuing shares and debentures or by taking loan
3. Private sector exploits the workers.
4. It allows concentrate of huge wealth in few hands or rich people Eg-TVS Motors, Ashok Leyland, TATA Steel.
5. Tax evasion is possible
6. It is purely profit oriented
7. It does not care the socially backward class, Reservation is not followed.

Question 6.
Write the functions of private sector.
Answer:
Functions of Private Sector are given below:

1. The main function of private sector is to create innovation and modernization.
2. Develop and maintain infrastructure and services.
3. Promote and expand existing businesses.
4. Promote human capital development, to help vulnerable groups.
5. Promote small, micro and medium enterprises (SMME) through supply side measures, and demand side measures and attract investment in the city.
6. The Government has fixed a specific role to the private sector in the field of industries, trade and services sector.

VIII. Activity:
Question 1.
Life expenctancy – ability to lead a long and health life. Explain your reasons for the classification.
Answer:
Activity to be done by the students themselves

IX. Life Skills:

Question 1.
Teacher and students are discuss about the Socio – Economic Development and industrial growth and development in that locality.
Answer:
Activity to be done by the students themselves

Samacheer Kalvi 8th Social Science Economics Public and Private Sectors Additional Questions

I. Choose the correct answer:

Question 1.
The public sector enables the full growth in ………………..
(a) Politics
(b) Education
(c) An Economy
(d) None of the above
Answer:
(c) An Economy

Question 2.
The planning Commission was formed in ………………..
(a) 1950
(b) 1947
(c) 1951
(d) 1949
Answer:
(a) 1950

Question 3.
‘The Father of Public sector undertakings in India’ denotes to ………………..
(a) Dr. V. Krishnamurthy
(b) Jawaharlal Nehru
(c) Rajaji
(d) None of the above
Answer:
(a) Dr. V. Krishnamurthy

Question 4.
Which of the following does / do come under administration by a Government Department?
(a) Port and Telegraph
(b) Railways
(c) Irrigation projects
(d) All of the above
Answer:
(d) All of the above

Question 5.
Indian Synthetic Rubber Ltd comes under …………………
(a) Joint sector
(b) Private sector
(c) Public sector
(d) Public Corporation
Answer:
(a) Joint sector

Question 6.
National Health Production Scheme serves ………………..
(a) poor
(b) vulnerable families, none of the above
(c) both (a) and (b)
(d) none of the above
Answer:
(c) both (a) and (b)

Question 7.
The life cycle of the people increases due to ………………..
(a) Housing facilities
(b) Clean drinking water facilities
(c) Sanitary facilities
(d) All of the above
Answer:
(d) All of the above

Question 8.
Heavy and basic industries refer to ………………..
(a) Iron and Steel
(b) Shipping
(c) Mining
(d) All of the above
Answer:
(d) All of the above

II. Fill in the blanks:

1. Mixture of capitation and socialism is called …………….
2. The sector, which is engaged in the activities of providing government goods and services to the general public is …………….
3. In 1947, India was primarily an ……………. country.
4. The first Industrial Policy resolution was announced in …………….
5. Indian statistician ……………. was instrumental to the formulation of public sector undertakings in India.
6. The 1991 industrial policy gave more freedom to the ……………. sector.
7. LIC, Air India, The Reserve Bank of India, Electricity Board come under the ……………. type of organisation.
8. NITI Aayog refers to …………….
9.  ……………. is government of India’s flagship programme.
10. National Gas Commission (ONGC) has saved foreign exchange by way of …………….
11. The largest public sector employer in India is …………….
12. Though the public sector and private sector work together for developing the country, they have ……………. goals and motives.
13. Tata group of companies come under ……………. sector.

Answer:

1. Mixed economy
2. Public sector
3. Agricultural
4. 1948
5. P.C. Mahalanobis
6. Private
7. Public Corporation
8. National Institution for Transforming India
9. Sarva Siksha Abhivan(SSA)
10. Import Substitution
11. Indian Railways
12. different
13. Private

III. Match the following:

1. FCI – (a) Sarva Siksha Abhiyan
2. NHPS – (b) State Trading Corporation
3. SSA – (c) National Aluminium Company
4. STC – (d) Food Corporation of India
5. NALCO – (e) National Health Production Scheme

Answer:

1. d
2. e
3. a
4. b
5. c

IV. Which is the Odd one:

Question 1.
(a) SAIL
(b) BHEL
(c) GAIL
(d) EIL
Answer:
(d) EIL

V. Which of the following is a correct answers:

(i) Public sector and capital formation is very important during the planning period.
(ii) Public sector undertaking have located their plants in well developed areas.
(iii) Public sector has created millions of jobs to tackle the unemployment problem in the country.

(a) All are Correct
(b) (i) and (iii) are Correct
(c) (i) and (ii) are Correct
(d) None of these
Answer:
(b) (i) and (iii) are Correct]Answer in one or two sentences:

VI. Answer in one or two sentences:

Question 1.
What type of economy was promoted by Jawaharlal Nehru?
Answer:
Prime Minister Jawaharlal Nehru promoted an economic policy based on import substitution industrialisation and advocated a mixed economic system.

Question 2.
What is Schedule – A?
Answer:

1. The public sector in India owes its origin in the 1956 Industrial policy resolution of the Government of India.
2. It classified the industries into three categories.
3. The Industries which would be exclusively owned by the state are referred to as Schedule-A.

Question 3.
What is Schedule – B?
Answer:

1. The industries in which the private sector could supplement the efforts of the state sector.
2. The state taking the sole responsibility for starting new units which are specific in Schedule-B.

Question 4.
Explain Term NITI Aayog.
Answer:

1. NITI Aayog (National Institution for Transforming India) replaced 65 years old planning commission.
2. NITI Aayog is essentially a“Think Tank” and a truly advisory body.

Question 5.
What do you meant by the term ‘Smart City’?
Answer:

1. A growing number of people moved urban areas in search of employment.
2. Hence Government started the ‘ Smart city’ Scheme which provides the city with many facilities like hospitals, schools, housing facilities and shopping centers.

Question 6.
Explain the term ‘Navaratna’.
Answer:

1. The term Navaratna meant a talisman composed of nine precious gems.
2. Later, this term was adopted in the courts of Gupta emperor Vikramaditya and Mughal emperor Akbar as the collective name for nine extraordinary courtiers at their respective courts.

VII. Answer the following in detail:

Qustion 1.
Write about the categories of the public sector.
Answer.
Public Sector is divided into the following nine categories:

1. Public sector enterprises must supply essential infrastructure for economic development which are known as primary public utilities which include the following : Airlines, Shipping, Railways, Power Generation, Tele communication etc.
2. Public sector enterprises also to have control of the commanding heights of the economy e.g. Defence, Banks, Coalmines, Oil, Steel etc.
3. They are to play an entrepreneurial role called capital intensive industries such as Iron ore, Petro-Chemicals, Fertilizer, Mining etc.
4. Public sector enterprises under Government monopoly which includes: Telecommunication equipment, Defence production etc.
5. Public sector enterprises exclusively meant for High Technology like Atomic energy.
6. Consumer oriented public sector undertakings like Drug, Paper, Hotels etc. Public Sector enterprise which is set up in order to take sick private units like Textile, Engineering etc.
7. Public sector enterprises set up as Trade Corporation such as FCI, CCI etc.
8. Public sector enterprises which serve as a consultancy and engineering service etc. Eg. MECON.

Students can Download Science Term 3 Chapter 2 Magnetism Questions and Answers, Notes Pdf, Samacheer Kalvi 8th Science Book Solutions Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus and score more marks in your examinations.

Tamilnadu Samacheer Kalvi 8th Science Solutions Term 3 Chapter 2 Magnetism

Samacheer Kalvi 8th Science Magnetism Text Book Exercises

I. Choose the best answer:

8th Science Magnetism Question 1.
A magnet attracts ………………
(a) wooden materials
(b) any metal
(c) copper
(d) iron and steel
Answer:
(d) iron and steel

Magnetism 8th Class Question 2.
One of the following is an example for a permanent magnet.
(a) Electromagnet
(b) Mumetal
(c) Soft iron
(d) Neodymium
Answer:
(d) Neodymium

A Magnet Attracts Answer Question 3.
The south pole of a bar magnet and the north pole of a U-shaped magnet will ……………….
(a) attract each other
(b) repel each other
(c) neither attract nor repel each other
(d) None of the above
Answer:
(a) attract each other

Samacheer Kalvi 8th Science Book Solutions Question 4.
The shape of the Earth’s magnetic field resembles that of an imaginary ………………
(a) U-shaped magnet
(b) straight conductor carrying current
(c) solenoid coil
(d) bar magnet
Answer:
(d) bar magnet

Samacheer Kalvi Guru 8th Question 5.
MRI stands for………………
(a) Magnetic Running Image
(b) detection of magnetic field
(c) navigation
(d) Magnetic Radar Imaging
Answer:
(a) Magnetic Resonance Imaging

Magnetising Magnets Question 6.
A compass is used for ………………
(a) plotting magnetic lines
(b) detection of magnetic field
(c) navigation
(d) All of these
Answer:
(d) All of these

II. Fill in the blanks:

1. The magnetic strength is …………… at the poles.
2. A magnet has …………… magnetic poles.
3. Magnets are used in …………… for generating electricity.
4. …………… are used to lift heavy iron pieces.
5. A freely suspended bar magnet is always pointing along the …………… north-south direction.

Answer:

1. maximum
2. two
3. dynamos
4. Electromagnets
5. geographic

III. Match the following:

1. Magnetite – Magnetic lines Natural
2. A tiny pivoted magnet – magnet
3. Cobalt – Compass box
4. Closed curves – Ferromagnetic material
5. Bismuth – Diamagnetic material

Answer:

1. Magnetite – Natural magnet
2. A tiny pivoted magnet – Compass box
3. Cobalt – Ferromagnetic material
4. Closed curves – Magnetic lines
5. Bismuth – Diamagnetic material

IV. Choose the correct option:

(a) If both assertion and reason are true and reason is the correct explanation of the assertion.
(b) If both assertion and reason are true but reason is not the correct explanation of assertion.
(c) If the assertion is true, but the reason is false.
(d) If the assertion is false, but the reason is true.

Question 1.
Assertion: Iron filings are concentrated more at the magnetic poles.
Reason: The magnets are so sharp.
Answer:
(b) Both assertion and reason are true but reason is not the correct explanation of assertion.

Question 2.
Assertion: The Earth’s magnetic field is due to iron present in its core.
Reason: At a high temperature, a magnet loses its magnetic property or magnetism.
Answer:
(d) Assertion is false but the reason is true.

Correct statement:
The Earth’s magnetic field is due to the molten charged metallic fluid inside the Earth’s surface.

V. Answer briefly:

Question 1.
What is magnetic field?
Answer:
The space around a magnet in which its magnetic effect or influence is observed.

Question 2.
What is artificial magnet? Give examples.
Answer:
Magnets that are made by people in a laboratory or a factory are called artificial magnets.
Example:
Horse shoe magnet, bar magnet, U-shaped magnet, cylindrical magnets, disc magnets, ring magnets and electromagnets.

Question 3.
Distinguish between natural and artificial magnets.
Answer:
1. Natural Magnets:

• These are found in nature.
• Have irregular shapes and dimensions.
• The strength of a natural magnet is well determined and difficult to change.
• These are permanent magnets.
• They have a less usage.

2. Artificial Magnets:

• These are man-made magnets.
• They can be made in different shapes and dimensions.
• Artificial magnets can be made with required and specific strength.
• Their properties are time bound.
  They have a vast usage in day-to-day life.

Question 4.
Earth acts as a huge bar magnet. Why? Give reasons.
Answer:

1. A freely suspended magnetic needle at a point on the Earth comes to rest approximately along the geographical north – south direction.
2. This shows that the Earth behaves like a huge magnetic dipole with its magnetic poles located near its geographical poles.
3. The north pole of a magnetic needle approximately points towards the geographic north (NG).
4. The magnetic north pole of the needle is attracted by the magnetic south pole of the Earth (Sm), which is located at the geographic north NG.
5. Also, the magnetic south pole of the needle is attracted by the magnetic north pole of the Earth (Nm), which is located at the geographic south SG.

Question 5.
How can you identify non-magnetic materials? Give an example of a non- magnetic material.
Answer:

1. Materials which are not attracted by magnets are called non-magnetic materials.
2. Example: Wood, Glass, Rubber, Plastic, Aluminium.

VI. Answer in detail:

Question 1.
List out the uses of magnets in day-to-day life.
Answer:

1. In ancient times, the magnet in the form of ‘direction stone’ helped seamen to find the directions during a voyage.
2. Nowadays, magnets are used to generate electricity in dynamos.
3. Electromagnets are used in our day-to-day life.
4. They are used in electric bells and electric motors.
5. They are used in loudspeakers and microphones.
6. An extremely powerful electromagnet is used in the fast moving Maglev train to remain floating above the tracks.
7. In industries, magnetic conveyor belts are used to sort out magnetic substances from scraps mixed with non-magnetic substances.
8. Magnets are used in computer in its storing devices such as hard disks.
9. In banks, the magnets enable the computers to read the MICR numbers printed on a cheque.
10. The tip of the screw drivers are made slightly magnetic so that the screws remain attached to the tip.
11. At hospitals, extremely strong electro magnets are used in the MRI (Magnetic Resonance Imaging) to scan the specified internal organ.

Question 2.
How will you convert a ‘nail’ into a temporary magnet?
Answer:

1. Spread some steel pins on a wooden board and bring an iron nail near them.
2. Now, make one of the magnetic poles of the bar magnet touch one end of the iron nail.
3. Slide it along its length in one direction slowly till the other end is reached.
4. Repeat the process, as shown in the diagram, 20 to 30 times.
5. The magnet has to be moved in one direction only.
6. Avoid the swiping of the magnet back and forth.
7. Now, bring the iron nail near the steel pins.
8. The steel pins stick to the iron nail because nail has become a temporary magnet.

Question 3.
Write a note on Earth’s magnetism.
Answer:

1. Earth has been assumed or imagined by the scientists as a huge magnetic dipole.
2. The south pole of the imaginary magnet inside the Earth is located near the geographic north pole and the north pole of the Earth’s magnet is located near the geographic south pole.
3. The line joining these magnetic poles is called the magnetic axis.
4. The magnetic axis intersects the geographic north pole at a point called the north geomagnetic pole or northern magnetic pole.
5. It intersects the geographic south pole at a point called the south geomagnetic pole or southern magnetic pole.
6. The magnetic axis and the geographical axis (axis of rotation) do not coincide with each other.
7. The cause of the Earth’s magnetism, are as follows.
   • Masses of magnetic substances in the Earth
   • Radiations from the Sun
   • Action of the Moon

VII. Higher Order Thinking Questions:

Question 1.
Though Earth is acting as a huge bar magnet it is not attracting other ferromagnetic materials. Why? Give reasons.
Answer:
Earth is not attracting other ferromagnetic materials because the magnetic character of ferromagnetic materials is affected by the external temperature. When they are heated, they become paramagnetic at curie temperature.

Question 2.
Why it is not advisable to slide a magnet on an iron bar back and forth during magnetising it?
Answer:
It is not advisable to slide a magnet on an iron bar back and forth because moving it in opposite directions will work to cancel each other out.

Question 3.
Thalami Dharaga and Sangamithirai were playing with a bar magnet. They put the magnet down and it broke into four pieces. How many poles will be there?
Answer:
Each broken piece behaves like a separate magnet. Therefore, four pieces will have eight poles.

Conclusion:
Thus, we can conclude that unlike poles of a magnet attract each other, i.e., the north pole and the south pole of a magnet attract each other.

Samacheer Kalvi 8th Science Magnetism Additional Questions

I. Choose the correct answer:

Question 1.
It is believed that the had known the property of magnet even before 200 BC.
(a) Indians
(b) Japanese
(c) Chinese
(d) Americans
Answer:
(c) Chinese

Question 2.
is the ore of iron which is the strongest natural magnet.
(a) Iron oxide
(b) Iron sulphide
(c) Ferrite
(d) Columbine
Answer:
(a) Iron oxide

Question 3.
Who laid the foundation for magnetism and suggested that the Earth has a giant bar magnet?
(a) Einstein
(b) Newton
(c) Galileo
(d) William Gilbert
Answer:
(d) William Gilbert

Question 4.
Attractive property of a magnet is more at the………
(a) North pole
(b) South pole
(c) both a & b
(d) middle
Answer:
(d) both a & b

IV. Match the following:

1. Directive property – (a) Never intersect
2. Magnetic poles – (b) Magnetic compass
3. Lines of force – (c) Attract
4. Unlike poles – (d) Exist in pairs

Answer:

1. b
2. d
3. a
4. c

V. Very short answer questions:

Question 1.
What is the other name of lodestone?
Answer:
Magnetite. (Iron oxide)

Question 2.
Convert 1 tesla into gauss.
Answer:
1 tesla = 10, 000 gauss.

Question 3.
Name a few paramagnetic substances.
Answer:
Aluminium, Platinum, Chromium, Oxygen and Manganese.

Question 4.
How artificial magnets are produced?
Answer:
Artificial magnets are produced by stroking a magnetic material with magnetite or with other artificial magnets.

Question 5.
What is the diameter of the magnetar?
Answer:
The diameter of the magnetar is 20 km.

Question 6.
Name the strongest and the most powerful magnets on the Earth.
Answer:
Neodymium magnets.

Question 7.
Name the most commonly used permanent magnet.
Answer:
ALNICO. (An alloy of aluminium, nickel and cobalt)

Question 8.
What is meant by magnetic axis?
Answer:
The line joining the magnetic poles is called the magnetic axis.

Question 9.
What type of magnet used in Mangle train?
Answer:
An extremely powerful electromagnet is used in Mangle train.

Question 10.
What is meant by a mag-stripe?
Answer:
The strip on the back of a credit card / debit card is a magnetic strip, often called mag-stripe.

VI. Short Answer type Questions:

Question 1.
Write a note on magneto – reception.
Answer:

1. Pigeons have extraordinary navigational abilities.
2. It enables them to find their way back home even if you take them to a place where they have never been before.
3. The presence of magnetite in their beaks enables them to sense the magnetic field of the Earth.
4. Such a magnetic sense is called magneto-reception.

Question 2.
Mention any two uses of magnets.
Answer:

1. In ancient times, the magnet in the form of ‘direction stone helped seamen to find the directions during a voyage.
2. Magnets are used in computer in its storing devices such as hard disks.

Question 3.
Write a note on Mangle train.
Answer:

1. Mangle train (Magnetic levitation train) has no wheels.
2. It floats above its tracks due to strong magnetic forces applied by computer controlled electromagnets.
3. It is the fastest train in the world. The speed attained by this train is around 500 km/hr.

Question 4.
What is magnetization?
Answer:

1. Magnetization is a process in which a substance is made a permanent or temporary magnet by exposing it to an external magnetic field.
2. This is one of the methods to produce artificial magnets.

Question 5.
Write a note on Magnetar.
Answer:
The most powerful magnet in the Universe is actually a neutron star called Magnetar:

1. Located in the Milky Way Galaxy.
2. The diameter of the magnetar is 20 kilometer and its mass is 2 to 3 times than that of the Sun.
3. Its magnetic field is so enormous and lethal that it is capable of absorbing all the iron atoms from the bloodstream (hemoglobin) of a living body even if it is positioned at a distance of 1000 km from it.

Question 6.
Mention the properties of a magnet.
Answer:
Repulsive:

1. Attractive property a magnet always attracts materials like iron, cobalt and nickel
2. Property another property of a magnet that like poles repel each other i.e., a north pole repels another north pole and a south pole repels another south pole.
3. Directive property the property of a magnet, by which it aligns itself along the geographic north-south direction, when it is freely suspended, is known as the directive property of a magnet.

Question 7.
Give some examples of artificial magnets.
Answer:
Bar magnets, U-shaped magnets, horseshoe magnets, cylindrical magnets, disc magnets, ring magnets and electromagnets are some examples of artificial magnets.

Question 8.
Mention the three types of iron ores.
Answer:
Hematite (69% of Iron), Magnetite (72.4% of Iron) and Side-rite (48.2% of Iron). Magnetite is an oxide ore of iron with the formula Fe 304. Among these ores, Magnetite has more magnetic property.

VII. Long answer questions:

Question 1.
Write a note on:

1. Compass needle
2. Mag-stripe.

Answer:
1. Compass needle:

• A compass needle, also known as plotting compass or magnetic needle, consists of a tiny pivoted magnet in the form of a pointer, which can rotate freely in the horizontal plane.
• The ends of the compass needle point approximately towards the geographic north and south direction.

2. Magstripe:

• A strip on the back of a credit card/debit card is a magnetic strip, often called a magstripe.
• The magstripe is made up of tiny iron-based magnetic particles in a thin plastic film.

Samacheer Kalvi 8th Science Magnetism Intext Activities

Activity -1

Take some iron filings in a paper and place a magnet near them. Do you see the iron filings being attracted by the magnet? In which part of the magnet they are attracted?
Answer:
The iron filings are attracted near the ends of the magnet. These ends are called poles of a magnet.

Conclusion:
This shows that the attractive property of a magnetis more at the poles.

Activity – 2

Take a bar magnet and suspend it from a support. Hold another bar magnet in your hand. Bring the north pole of this magnet close to the north pole of the suspended magnet. What do you see? The north pole of the suspended magnet will move away.

Answer:
Inference:
This activity explains repulsive property of a magnet that like poles repel each other i.e., a north pole repels another north pole and a south pole repels another south pole. If you bring the south pole of the magnet close to the north pole of the suspended magnet you can see that the south pole of the suspended magnet is immediately attracted.

Activity – 3

Suspend a bar magnet from a rigid support using a thread. Ensure that there are no magnetic substances placed near it. Gently disturb the suspended magnet. Wait for a moment, let it oscillate. In a short time, it will come to rest. You can see that the north pole of the magnet is directed towards the geographic north. Repeat the procedure a number of times. You will observe that the magnet is oriented in the same direction.

Answer:
The magnet is oriented in the same direction. This experiment shows that a freely suspended bar magnet always aligns itself in the geographic north-south direction.

Conclusion:
The property of a magnet, by which it aligns itself along the geographic north- south direction, when it is freely suspended, is known as the directive property of a magnet.

Activity – 4

Spread some iron filings which are collected from the sand uniformly on a sheet of white paper placed on a table. Place a bar magnet below the white sheet. Gently tap the table. What do you see? You can see the pattern as shown in the figure.

Answer:
I can see the iron filings are arranged in the form of curved patterns around the magnet. The space around the bar magnet where the arrangement of iron filings exists, represents the field of influence of the bar magnet. It is called the magnetic field.

Activity – 5

Spread some iron pins, stapler pins, iron nails, small pieces of paper, a scale, an eraser and a plastic cloth hanger on a wooden table. Place a magnet nearby these materials. What do you observe? List out which of these things are attracted by the magnet? Which objects are not attracted? Tabulate your observations.
Answer:
Aim:
To understand the behavior of magnetic and non-magnetic materials.
1. Materials attracted by magnet:

• Iron pins
• Stapler pins
• Iron nails

2. Materials not attracted by magnet:

• Small pieces of paper
• Scale
• Eraser
• Plastic cloth hanger

Students can Download Science Term 3 Chapter 5 Acids and Bases Questions and Answers, Notes Pdf, Samacheer Kalvi 8th Science Book Solutions Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus and score more marks in your examinations.

Tamilnadu Samacheer Kalvi 8th Science Solutions Term 3 Chapter 5 Acids and Bases

Samacheer Kalvi 8th Science Acids and Bases Text Book Exercise

I. Choose the best answer:

8th Science Acid And Base Question 1.
Acids are ……………. in taste.
(a) sour
(b) sweet
(c) bitter
(d) salty
Answer:
(a) sour

Acids Bases And Salts Samacheer Kalvi Question 2.
Aqueous solutions of ……………. conduct electricity.
(a) acid
(b) base
(c) salt
(d) salt and base
Answer:
(d) salt and base

Acids, Bases And Salts Samacheer Kalvi Question 3.
In acidic solution, blue litmus changes into ……………. colour.
(a) blue
(b) green
(c) red
(d) white
Answer:
(c) red

Samacheer Kalvi Guru 8th Science Question 4.
Base is a substance that gives ……………. on dissolving in water.
(a) OH^–
(b) H⁺
(c) OH
(d) H
Answer:
(a) OH

8th Grade Science Acids And Bases Question 5.
Sodium hydroxide is a …………….
(a) acid
(b) base
(c) oxide
(d) alkali
Answer:
(d) alkali

Question 6.
Red ant sting contains …………….
(a) acetic acid
(b sulphuric acid
(c) oxalic acid
(d) formic acid
Answer:
(d) formic acid

Question 7.
Magnesium oxides are used for treating …………….
(a) acidity
(b) head pain
(c) teeth decay
(d) None of these
Answer:
(a) acidity

Question 8.
Acid mixed with base forms …………….
(a) salt and water
(b) salt
(c) water
(d) no reaction
Answer:
(a) salt and water

Question 9.
We brush our teeth with tooth paste because it is …………….
(a) basic
(b) acidic
(c) both a and b
(d) none of these
Answer:
(a) basic

Question 10.
In basic solution turmeric indicator paper changes from yellow to …………….
(a) blue
(b) green
(c) yellow
(d) red
Answer:
(d) red

II. Fill in the blanks:

1. Benzoic acids are used for …………
2. The word sour refers to ………… in Latin.
3. Bases are ………… in taste.
4. Chemical formulae of calcium oxide is …………
5. Wasp sting contains …………
6. Turmeric is used as a …………
7. In acidic solution, the colour of the hibiscus indicator paper will change to …………

Answer:

1. preservation of food
2. acidus
3. bitter
4. CaO
5. alkaline substance
6. indicator
7. deep pink or deep red

III. State True or False. If false, correct the statement:

Question 1.
Most of the acids are not soluble in water.
Answer:
True.

Question 2.
Acids are bitter in taste.
Answer:
False
Correct statement:
Acids are sour in taste. Bases are bitter in taste.

Question 3.
Bases are soapy to touch when they are dry.
Answer:
False
Correct statement:
Bases are soapy to touch only in aqueous media, not in dry nature.

Question 4.
Acids are corrosive in nature.
Answer:
True

Question 5.
All bases are alkalis.
Answer:
False
Correct statement:
All alkalis are base, but all bases are not alkalis.

Question 6.
Hibiscus flower is an example for natural indicator.
Answer:
True

IV. Answer briefly:

Question 1.
Define acid.
Answer:
A substance which contains one or more replaceable hydrogen atoms.

Question 2.
Write any four physical properties of acids.
Answer:

1. Acids are sour in taste.
2. They are corrosive in nature. Strong acids can spoil substances like human skin, clothes and paper.
3. Generally acids exist in liquid state but few acids exist in solid state too. E.g. Benzoic acid.
4. Acids are colourless.
5. Acids change the colour of the indicators. Blue litmus paper turns red and methyl orange turns pink when treated with acids.

Question 3.
What are the similarities between acids and bases?
Answer:

1. They are corrosive in nature.
2. They undergo ionization in aqueous solution.
3. They conduct electricity in aqueous solution.
4. They undergo neutralization reaction.

Question 4.
State the difference between acids and bases.
Answer:
Difference between acids and bases:
Acids:

1. They produce H⁺ ions in water.
2. They are sour in taste.
3. Few acids are in solid state.
4. Acids turn blue litmus paper red.

Bases:

1. They produce OH^– ions in water.
2. They are bitter in taste.
3. Most of the bases are in solid state.
4. Bases turn red litmus paper blue.

Question 5.
What is an indicator?
Answer:
An indicator or acid – base indicator is a chemical substance which indicates the acidic or basic nature of a solution by suitable colour change.

Question 6.
What is a neutralization reaction?
Answer:
Neutralization is a chemical reaction in which an acid and a base react with each other to form water and salt.

Question 7.
Write any four physical properties of base.
Answer:

1. Bases generally exist in solid state but some bases exist in liquid state also. E.g. Ammonium hydroxide, calcium hydroxide.
2. Bases give soapy touch only in aqueous media not in dry nature.
3. Bases are bitter in taste.
4. Bases are corrosive in nature. When come in contact with the skin frequently they form painful blisters.
5. Bases also change the colour of the indicators. Red litmus paper turns blue when . treated with bases. Similarly, they turn methyl orange yellow and phenolphthalein pink.

V. Answer in detail:

Question 1.
What are the uses of acids?
Answer:

1. Hydrochloric acid present in our stomach helps in the digestion of foodstuff.
2. Vinegar (acetic acid) is used to preserve food materials.
3. Benzoic acid is also used to preserve food materials like pickles.
4. Sodium or potassium salts of higher fatty acids are used to make washing and bathing soaps.
5. Sulphuric acid is called the king of chemicals. It is an effective dehydrating agent. It is used in various industries to make detergents, paints, fertilizers and many more chemicals.
6. Hydrochloric acid, Nitric acid and Sulphuric acid are important laboratory reagents.
7. Cells of all living organisms contain the fundamental nuclear material called nucleic acids. Animals have deoxyribo nucleic acid (DNA) whereas plants contain ribo nucleic acid (RNA).

Question 2.
What are the uses of bases?
Answer:

1. Potassium hydroxide is used to make bathing soaps.
2. Sodium hydroxide is used to make washing soaps.
3. Sodium hydroxide is also used in paper industries, textile industries and in the preparation of medicines.
4. Calcium hydroxide is used for white washing.
5. Aluminum hydroxide and magnesium hydroxides are used in antacids to cure acidity problems.
6. Ammonium hydroxide is used to manufacture fertilizers, nylon, plastics and rubber.

Question 3.
Explain the neutralization reaction in our daily life.
Answer:
1. Ant bite:

• Whenever bees or red ants bite they inject an acid called formic acid.
• These acids cause burning sensation and pain.
• To suppress the pain, a suitable base in the form of calcium hydroxide (readily available at home) is applied to neutralise the formic acid.

2. Wasp bite:

• When we are bitten by wasp, we feel the burning sensation and pain. It is due to an alkaline substance injected by the insect.
• To neutralise the alkalinity, we use vinegar which is an acid.

3. Tooth decay:

• The bacteria present in our mouth decompose the food particles stuck in the gaps between our teeth thereby causing acid formation which leads to tooth decay.
• When we brush with tooth powder or tooth paste containing weak bases, the acid gets neutralized.

4. Acidity:

• Excessive production of hydrochloric acid in our stomach causes ulcer in stomach and food pipe.
• In order to neutralize, antacids which are nothing but weak bases like aluminum and magnesium hydroxides are used.

5. Agriculture:
Farmers add lime fertilisers such as powdered lime (CaO), limestone (CaCO₃) or ashes of
burnt wood to the soil to neutralise the acidity.

6. Industries:
Effluents from the industries contain acids such as sulphuric acid. It is treated by adding lime to neutralise it before it is discharged into rivers and streams.

Question 4.
How will you prepare natural indicator from turmeric powder?
Answer:

1. Turmeric indicator is one of the natural indicator.
2. By adding small amount of water to turmeric powder, a paste is prepared.
3. This is applied on a blotting paper or filter paper and dried.
4. These strips are used as indicators to find the nature of the solution.
5. In acidic solution, turmeric indicator paper has no change in colour.
6. That means, it remains yellow. In basic solution, the colour changes from yellow to red.

VI. Higher Order Thinking Questions:

Question 1.
Vinu and Priyan take their lunch at school. Vinu eats lemon rice and Priyan eats curd rice. Both lemon rice and curd rice are sour in taste. What is the reason?
Answer:

1. Curd contains lactic acid. The lactic acid makes curd rice sour in taste.
2. Lemon juice contains citric acid. The citric acid makes lemon rice sour in taste.
3. Generally acids are sour in taste.

Question 2.
Heshna and Keerthi are friends. Keerthi’s teeth are white without caries, but Heshna has teeth with caries. Why? How is it formed?
Answer:

1. Caries is caused by the action of acids on the enamel surface.
2. The acid is produced when sugar in foods or drinks react with bacteria present on the tooth surface.
3. Heshna has not cleaned her teeth well after sipping sugary drinks and snacking.
4. She has to brush after meals and before bed.

Samacheer Kalvi 8th Science Acids and Bases Additional Questions

I. Choose the correct answer:

Question 1.
Acids present in fruits and vegetables are called ……………… acids.
(a) organic
(b) strong
(c) mineral
(d) fruit
Answer:
(a) organic

Question 2.
Vinegar is ……………… in taste.
(a) bitter
(b) sour
(c) sweet
(d) sweetless
Answer:
(b) sour

Question 3.
Citric acid is present in ………………
(a) curd
(b) milk
(c) lemon
(d) spinach
Answer:
(c) lemon

Question 4.
Which of the following is not a natural indicator?
(a) Litmus
(d) Turmeric
(c) Methyl orange
(d) Hibiscus
Answer:
(c) Methyl orange

Question 5.
An acid is ………………
(a) bitter is taste
(d) soapy to touch
(c) corrosive in nature
(d) all the above
Answer:
(c) corrosive in nature

Question 6.
The common salt is ………………
(a) sodium carbonate
(b) sodium bicarbonate
(c) sodium nitrate
(d) sodium chloride
Answer:
(d) sodium chloride

Question 7.
Add few drops of hibiscus indicator in soap solution. What do you observe?
(a) It turns green
(b) It turns magenta
(c) It turns yellow
(d) It turns red
Answer:
(a) It turns green

Question 8.
Acids and bases can be identified in the laboratory by ………………
(a) an indicator
(b) tasting
(c) touching
(d) smelling
Answer:
(a) an indicator

Question 9.
Lemon juice will turn ……………….
(a) phenolphthalein pink
(b) red litmus blue
(c) turmeric indicator red
(d) methyl orange red
Answer:
(d) methyl orange red

Question 10.
A salt may be ………………
(a) acidic only
(b) basic only
(c) neutral only
(d) acidic, basic or neutral
Answer:
(d) acidic, basic or neutral

II. Fill in the blanks:

1. Acids are ……………… in taste.
2. Solutions of acids conduct ………………
3. ……………… change the colour of the indicators
4. ……………… is used to preserve food materials
5. ……………… is called the king of chemicals.
6. Bases are chemical substances that are corrosive and ……………… in nature
7. Water soluble bases are called ………………
8. Sodium carbonate is commercially called as ………………
9. Acidity or indigestion in stomach is due to excessive secretion of ………………
10. Methyl orange gives ……………… colour in an acidic solution.

Answer:

1. sour
2. electricity
3. Acids
4. Vinegar
5. Sulphuric acid
6. bitter
7. alkalis
8. Baking soda
9. hydrochloric acid
10. majenta

III. Match the following:

Question 1.

1. Wasp sting – (a) Milk of magnesia
2. Common salt – (b) Acetic acid
3. Organic acid – (c) Sodium chloride
4. Antacid – (d) Vinegar

Answer:

1. d
2. c
3. b
4. a

Question 2.

1. Sulphuric acid – (a) Weak base
2. Sodium hydroxide – (b) Strong acid
3. Acetic acid – (c) Strong base
4. Ammonium hydroxide – (d) Weak acid

Answer:

1. b
2. c
3. d
4. a

Question 3.

1. Sodium chloride – (a) Detergents
2. Sodium carbonate – (b) Purification of water
3. Sodium bicarbonate – (c) Taste to food
4. Potash alum – (d) Antacids

Answer:

1. c
2. a
3. d
4. b

IV. True or False – if false, give the correct statement:

Question 1.
Acids have a sour taste and they are soapy to touch.
Answer:
False

Correct statement:
Bases have a sour taste and they are soapy to touch.

Question 2.
Neutral substances do not bring about any change in colour of indicators.
Answer:
True

Question 3.
All bases are alkalis but all alkalis are not bases.
Answer:
False

Correct statement:
All alkalis are bases but all bases are not alkalis.

Question 4.
When an acid reacts with a base, neutralisation reaction takes place to give salt and water.
Answer:
True

Question 5.
Acids are corrosive in nature. They corrode metals hence are not stored in metal containers.
Answer:
True.

V. Assertion and Reason:

Mark the correct choice as:
(a) If both assertion and reason are true and the reason is the correct explanation of assertion.
(b) If both assertion and reason are true, but reason is not the correct explanation of assertion.
(c) If the assertion is true, but reason is false.
(d) If the assertion is false, but reason is true.
(e) If both assertion and reason are false.

Question 1.
Assertion: To neutralise the excess acid formed in the stomach, milk of magnesia is taken.
Reason: Milk of magnesia contains a base called magnesium hydroxide.
Answer:
(a) Both assertion and reason are true and the reason is the correct explanation of assertion.

Question 2.
Assertion: A salt is produced when an acid is neutralised by a base.
Reason: A salt can be acidic, basic or neutral.
Answer:
(c) Both assertion and reason are true, but reason is not the correct explanation of assertion.

Question 3.
Assertion: With some samples of acids and bases, turmeric paper turns red.
Reason: Such samples are acidic in nature.
Answer:
(c) Assertion is true, but reason is false.

Correct Reason:
Such samples are basic in natural.

Question 4.
Assertion: Methyl orange and phenolphthalein are natural indicators.
Reason: Methyl orange is yellow in colour while phenolphthalein is pink.
Answer:
(d) Both assertion and reason are false.

VI. Very short answer questions:

Question 1.
Write the chemical name and formula of baking soda.
Answer:
Chemical name:
Sodium hydrogencarbonate
Formula: NaHCO₃.

Question 2.
What is the colour of phenolphthalein in basic solution?
Answer:
Phenolphthalein is pink in basic solution.

Question 3.
Give names of any two natural indicators.
Answer:
Turmeric and Litmus.

Question 4.
Name the acid present in vinegar.
Answer:
Acetic acid.

Question 5.
Name any two synthetic acid-base indicators.
Answer:
Methyl orange, Phenolphthalein.

Question 6.
Which acid is present in milk?
Answer:
Lactic acid.

Question 7.
What is the reaction between an acid and a base called?
Answer:
Neutralisation reaction.

Question 8.
Name the base which is present in a window cleaner.
Answer:
Ammonium hydroxide.

Question 9.
Which chemical is used to neutralise the acidic soil?
Answer:
Quicklime.

Question 10.
Can we taste acids and bases to identify them?
Answer:
No, acids and bases are corrosive in nature.

VII. Short Answer Questions:

Question 1.
Are all acids corrosive in nature? Name few acids which are non-corrosive and may be part of our food.
Answer:
No, all acids are not corrosive in nature. Certain acids like acetic acid present in vinegar, citric acid present in citrus fruits, lactic acid present in curd, oxalic acid present in tomatoes, etc, are part of our food and non-corrosive in nature.

Question 2.
Write the important uses of hydrochloric acid and sulphuric acids.
Answer:

1. Uses of hydrochloric acid – Cleaning agent for toilets, important laboratory agents.
2. Uses of sulphuric acid –
   • Used in car batteries.
   • Used to prepare a large number of compounds.

Question 3.
How will you prepare china rose indicator?
Answer:

1. Collect some china rose petals and place them in a beaker.
2. Add some warm water, keep the mixture for some time till water becomes coloured.
3. This coloured water is used as an indicator.

Question 4.
Give an important use of neutralisation reaction in daily life.
Answer:

1. In our daily life, neutralisation reaction is used to cure indigestion.
2. Too much acid in the stomach causes indigestion.
3. An antacid such as milk of magnesia is used to neutralise the excessive acid.

Question 5.
What is the role of toothpaste in prevention of tooth decay?
Answer:
When we brush with tooth powder or tooth paste containing weak bases, the acid gets neutralized. So our teeth will be strong and healthy and can be protected from caries.

Question 6.
How to treat effluents from the industries?
Answer:

1. Effluents from the industries contain acids such as sulphuric acid.
2. It is treated by adding lime to neutralise it before it is discharged into rivers and streams.

Question 7.
Write the chemical equation for the reaction of bases with metal oxides.
Answer:

1. All bases react with non-metallic oxides to form salt and water.
2. Eg: Sodium hydroxide reacts with carbon dioxide to form sodium carbonate.
3. Sodium hydroxide + Carbon dioxide —> Sodium carbonate + Water
   NaOH + CO —> Na₂CO₃ + H₂O

Question 8.
Write the reaction between sulphuric acid and water.
Answer:
Sulphuric acid + Water → Hydrogen ion + Sulphate ion
H₂SO₄ + H₂O → 2H⁺ + \({ SO }_{ 4 }^{ 2- }\)

Question 9.
Complete the table

Answer:

VIII. Long answer questions:

Question 1.
Write a note on:

1. Ant bite
2. Wasp bite.

Answer:
1. Ant bite:

• Whenever bees or red ants bite they inject an acid called formic acid.
• These acids cause burning sensation and pain.
• To suppress the pain, a suitable base in the form of calcium hydroxide (readily available at home) is applied to neutralise the formic acid.

2. Wasp bite:

• When we are bitten by wasp, we feel the burning sensation and pain.
• It is due to an alkaline substance injected by the insect.
• To neutralize the alkalinity we use vinegar which is an acid to neutralise.

Question 2.
Write a note on:

1. Litmus
2. Phenolphthalein
3. Methyl orange

Answer:
1. Litmus:

• Litmus is the most common indicators used in the laboratories.
• Litmus is a natural indicator which is extracted from lichens.
• It is available in the form of solution or in the form of strips prepared by absorbing litmus solution on filter paper.
• It is either red or blue in colour.
• Blue litmus paper turns red in acidic solution and red litmus paper turns blue in the basic solution.

2. Phenolphthalein:

• Phenolphthalein is a colourless compound.
• Its alcoholic solution is used as an indicator.
• It is colourless in acidic solution but turns pink in basic solution.

3. Methyl orange:

• Solid methyl orange dissolved in hot water and its filtrate is used as an indicator.
• It turns red in acidic solution and yellow in basic solution.

IX. Higher Order Thinking Questions:

Question 1.
What is the difference between an ant sting and a wasp sting?
Answer:
1. Ant sting:
An ant sting is acidic as it contains formic acid while the wasp sting is basic in nature.

2. Wasp sting:
Ant sting can be neutralised by a base like baking soda while wasp sting is neutralised by an acid like vinegar (acetic acid).

Question 2.
Copper or brass cooking vessels are coated with tin metal. Why?
Answer:

1. Copper or brass cooking vessels are coated with tin metal (eyam).
2. If it is not coated, the organic acids present in the food materials will react with copper and make the food poisonous.
3. The tin isolates the vessel from the action of acids and prevents food poisoning.

X. Solve the crossword by using the clues that below:

Across:
1. The acid found in apples.
3. The ion formed when an acid is dissolved in water.
5. An indicator that remains colourless in an acid.
7. The gas liberated when dilute hydrochloric acid reacts with limestone.
9. A gas that dissolved in water to form ammonium hydroxide.

Down:
2. An acid used for cooking.
4. An acid that has three hydrogen atoms in its moelcule.
6. A reaction in which an acid reacts w’ith a base to form salt and water only.
8. A base that is soluble in water.
10. The chemical name of this compound is calcium hydroxide.

Answer:

Samacheer Kalvi 8th Science Acids and Bases Intext Activities

Activity – 1

Question 1.
Take a clean test tube with holder and pour some dilute hydrochloric acid. Add few pieces of magnesium ribbon pieces slowly. What do you observe? Now show a burning match stick near the mouth of the test tube. Do you hear any sound? The gas burns with a pop sound. From this it is observed that hydrogen gas has been formed due to the reaction between acid and metal.
Answer:
The gas bums with a pop sound. From this it is observed that hydrogen gas has been formed due to the reaction between acid and metal.

Activity – 2

Take some lemon juice in a tumbler and add baking soda slowly. What do you see? I What do you infer from this?
Answer:
Inference:
When lemon juice is mixed with baking soda, the new product CO₂ is formed with water and salt.

Activity- 3

Classify the following substances. Sodium oxide, Potassium hydroxide, Calcium oxide, Copper oxide, Calcium hydroxide, Ammonium hydroxide, Ferric hydroxide, Zinc oxide
Answer:

Activity – 4

Question 1.
Take a shirt with turmeric powder strain. Wash the shirt with soap. Do you observe any change in the colour? Why?
Answer:
Yes, the colour changes from yellow to red, because soapy solution is a base.

Activity – 5

Question 1.
Take a small beet root vegetable and cut it into pieces. Boil them in hot water and filter the extract. Take two test tubes. Take sodium hydroxide solution in one test tube and vinegar or lemon juice in another test tube. Add beet root extract slowly. Observe the colour change. What do you infer?
Answer:

1. Observation – When beetroot juice is added with sodium hydroxide solution it turns into greenish yellow shows that NaOH^– is a base.
2. When it is added with lemon juice, the colour of beetroot juice remains same shows that lemon juice is acidic.

Activity – 6

Find out the nature of the solution

Tamilnadu State Board New Syllabus Samacheer Kalvi 8th Tamil Book Solutions Guide Pdf Chapter 6.2 மழைச்சோறு Text Book Back Questions and Answers, Summary, Notes.

Tamilnadu Samacheer Kalvi 8th Tamil Solutions Chapter 6.2 மழைச்சோறு

கற்பவை கற்றபின்

Question 1.
உங்கள் பகுதியில் பாடப்படும் மழை தொடர்பான நாட்டுப்புறப் பாடல்களைத் தொகுத்து எழுதுக.
Answer:
பாடல் – 1

ஆத்தா மகமாயி வந்திடம்மா
ஆத்தா மகமாயி வந்திடம்மா
உனக்கு எத்தனையோ பூச செஞ்சோம்
உனக்கு எத்தனையோ பூச செஞ்சோம்
வாம்மா வாம்மா வந்து மழைய குடும்மா
குடும்மா கருத்தம்மா
பசி வயிறு புடுங்கு தம்மா
மழை பெய்யச் சொல்லம்மா
மழை பெய்யச் சொல்லம்மா

பாடல் – 2

மழையப்பா மழையப்பா
கொஞ்சம் வாப்பா
இத்தனை நாள் வயல்
காணாதது போதாதா?
என்ன அப்பா கோபம்
மகன்கள் பண்ண
தப்ப மன்னிக்க மாட்டியா?
மன்னிச்சு வாப்பா
மானங்காக்க வாப்பா
மனமிரங்கி வாப்பா
மழையப்பா மழையப்பா

பாடநூல் வினாக்கள்

சரியான விடையைத் தேர்ந்தெடுத்து எழுதுக.

Question 1.
கனத்த மழை என்னும் சொல்லின் பொருள் ………………………
அ) பெருமழை
ஆ) சிறு மழை
இ) எடை மிகுந்த மழை
ஈ) எடை குறைந்த மழை
Answer:
அ) பெருமழை

Question 2.
‘வாசலெல்லாம்’ என்னும் சொல்லைப் பிரித்து எழுதக் கிடைப்பது ……………………
அ) வாசல் + எல்லாம்
ஆ) வாசல் + எலாம்
இ) வாசம் + எல்லாம்
ஈ) வாசு + எல்லாம்
Answer:
அ) வாசல்+எல்லாம்

Question 3.
‘பெற்றெடுத்தோம்’ என்னும் சொல்லைப் பிரித்து எழுதக் கிடைப்பது ……………………
அ) பெறு + எடுத்தோம்
ஆ) பேறு + எடுத்தோம்
இ) பெற்ற + எடுத்தோம்
ஈ) பெற்று + எடுத்தோம்
Answer:
ஈ) பெற்று + எடுத்தோம்

Question 4.
கால் + இறங்கி என்பதனைச் சேர்த்தெழுதக் கிடைக்கும் சொல் …………………..
அ) கால்லிறங்கி
ஆ) காலிறங்கி
இ) கால் இறங்கி
ஈ) கால்றங்கி
Answer:
ஆ) காலிறங்கி

குறுவினா

Question 1.
மழைச்சோறு பாடலில் உழவர் படும் வேதனை எவ்வாறு கூறப்படுகிறது?
Answer:
(i) கடலைச் செடி, முருங்கைச் செடி, கருவேலங்காடு, காட்டுமல்லி என அனைத்தும் மழையில்லாமல் வாடிப்போனது. பெற்றெடுத்த குழந்தைகளின் பசியைத் தீர்க்க முடியவில்லை .

(ii) கலப்பை பிடிப்பவரின் கை சோர்ந்து விட்டது, ஏற்றம் இறைப்பவரின் மனம் தவிக்கிறது என்றும் இதற்குக் காரணம் மழை இல்லாமையே இன்று உழவர் வேதனைப் படுகின்றனர்.

Question 2.
மக்கள் ஊரைவிட்டு வெளியேறக் காரணம் என்ன?
Answer:
மழை இல்லாததால் உழவுத் தொழில் செய்ய முடியவில்லை. எனவே மக்கள் ஊரை விட்டு வெளியேறுகின்றனர்.

சிறுவினா

Question 1.
கோலம் கரையாத நிலையை மழைச்சோறு பாடல் எவ்வாறு விளக்குகிறது?
Answer:

• வாளியில் கரைத்த மாவால் வாசலில் கோலம் போட்டனர்.
• இந்தக் கோலத்தைக் கரைக்க மழை வரவில்லை !
• பானையில் மாவைக் கரைத்து, பாதை எல்லாம் கோலம் போட்டனர்.
• அந்தக் கோலம் கரைக்கவும் மழை வரவில்லை .

Question 2.
மழையின்மையால் செடிகள் வாடிய நிலையை விளக்குக.
Answer:

• கல் இல்லாத காட்டில் கடலைச் செடி நட்டு வளர்த்தார்கள். அதற்கும் மழை பெய்யவில்லை.
• முள் இல்லாத காட்டில் முருங்கைச் செடி நட்டு வளர்த்தார்கள். அதற்கும் மழை வரவில்லை .
• கருவேலங்காடும் மழையில்லாமல் பூக்கவில்லை.
• மழை இல்லாததால் காட்டு மல்லியும் பூக்கவில்லை.

Question 3.
மழைச்சோறு எடுத்தபின் எவ்வாறு மழை பெய்தது?
Answer:

• மழைச் சோறு எடுத்தபின், பேய் மழையாக ஊசிபோல கால் இறங்கி உலகமெல்லாம் பெய்கிறது.
• சிட்டுப் போல மின்னி மின்னி ஊரெங்கும் பெய்கிறது.
• ஊரெங்கும் செல்ல மழை பெய்கிறது.

சிந்தனை வினா

Question 1.
மழைவளம் பெருக நாம் செய்ய வேண்டுவன யாவை?
Answer:
மழை வளம் பெருக அதிகப்படியான மரங்களை நட்டு வளர்க்க வேண்டும். மரங்களை நட்டால் மட்டும் போதாது. அதனை நன்கு பராமரிக்க வேண்டும். எங்காவது மரங்கள் வெட்டப்படும் போது, அதனைத் தடுக்க வேண்டும். ஒவ்வொரு வீட்டிலும் மழைநீர் சேமிப்புத் தொட்டி கட்டாயம் வைக்க வேண்டும். மழை பெய்யும் காலங்களுக்கு முன் குளங்கள் குட்டைகளை தூர்வார வேண்டும்.

கூடுதல் வினாக்கள்

சரியான விடையைத் தேர்ந்தெடுத்து எழுதுக.

Question 1.
ஒரு நாட்டின் வளத்திற்கு அடிப்படையாக விளங்குவது …………………….
அ) மழை
ஆ) உணவு
இ) உடை
ஈ) பணம்
Answer:
அ) மழை

Question 2.
கல் இல்லாக் காட்டில் …………………….. போட்டனர்.
அ) முருங்கைச் செடி
ஆ) கடலைச் செடி
இ) கருவேல மரம்
ஈ) காட்டு மல்லி
Answer:
ஆ) கடலைச் செடி

Question 3.
முள்ளில்லா காட்டில் …………………. போட்டனர்.
அ) முருங்கைச் செடி
ஆ) கடலைச் செடி
இ) கருவேல மரம்
ஈ) காட்டு மல்லி
Answer:
அ) முருங்கைச் செடி

Question 4.
‘வனவாசம் சென்று விடுவோம்’ என்று கூறியவர் …………………..
அ) புலவர்
ஆ) குறவர்
இ) உழவர்
ஈ) மறவர்
Answer:
இ) உழவர்

குறுவினா

Question 1.
எங்கெல்லாம் கோலம் இடப்பட்டது?
Answer:
வாசல் மற்றும் பாதைகளில் கோலம் இடப்பட்டது.

Question 2.
கடலைச் செடி வாடக் காரணம் யாது?
Answer:
மழை இல்லாததால் கடலைச் செடி வாடியது.

Question 3.
எவற்றை உழவர்கள் தலையில் வைத்துச் செல்கின்றனர்?
Answer:
மழைச் சோறு வாங்கிய பானை, அகப்பை, பழைய முறம் ஆகியவற்றை உழவர்கள் தலையில் வைத்துச் செல்கின்றனர்.

Question 4.
சிட்டு போல மின்னியது எது?
Answer:
சிட்டு போல மின்னியது மழை.

சிறுவினா

Question 1.
மழைச் சோற்று நோன்பு பற்றிக் குறிப்பிடுக.
Answer:
(i) மழையில்லாமல் பஞ்சம் ஏற்படும் நேரங்களில் சிற்றூர் மக்கள் வீடு வீடாகச் சென்று உப்பில்லாத சோற்றை ஒரு பானையில் வாங்குவார்கள். ஊர்ப் பொது இடத்தில் வைத்து அனைவரும் பகிர்ந்து உண்பர்.

(ii) கொடிய பஞ்சத்தைக் காட்டும் அடையாளமாக இது நிகழும். இதனைக் கண்டு மனம் இரங்கி மழை பெய்யும் என்பது மக்களின் நம்பிக்கை. இதனை மழைச்சோற்று நோன்பு என்று கூறுவார்கள்.

சொல்லும் பொருளும்

பாதை – வழி
கனத்த – மிகுந்த
பெண்டுகளே – பெண்களே
சீமை – ஊர்

Students can Download Social Science Geography Term 3 Chapter 1 Industries Questions and Answers, Notes Pdf, Samacheer Kalvi 8th Social Science Book Solutions Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus and score more marks in your examinations.

Tamilnadu Samacheer Kalvi 8th Social Science Geography Solutions Term 3 Chapter 1 Industries

Samacheer Kalvi 8th Social Science Geography Industries Textual Evaluation

I. Choose the correct answer:

Samacheer Kalvi 8th Social Book Solutions Question 1.
Silk weaving and house hold industries come under the category of ……………
(a) Small scale industry
(b) Large scale industry
(c) Marine based industry
(d) Capital intensive industry
Answer:
(a) Small scale industry

Samacheer Kalvi 8th Social Science Question 2.
On the basis of ownership the industry can be divided into ………….. types.
(a) 2
(b) 3
(c) 4
(d) 5
Answer:
(c)4

Samacheer Kalvi Guru 8th Social Science Question 3.
Amul dairy industry is best example of ………….. sector.
(a) Private Sector
(b) Public Sector
(c) Co-operative Sector
(d) Joint Sector
Answer:
(c) Co-operative sector

8th Standard Samacheer Kalvi Social Question 4.
Iron and Steel and Cement Industries are the examples of ………….. industries.
(a) Agro based
(b) Mineral based
(c) Forest based
(d) Marine based
Answer:
(b) Mineral based

8th Social Samacheer Kalvi Question 5.
Tertiary activity is divided into ………….. types
(a) 4
(b) 3
(c) 2
(d) 5
Answer:
(c) 2

II. Fill in the Blanks:

1. Banking is a ………….. economic activity.
2. Tertiary activity is divided into ………….. and …………..
3. Government decision making process comes under the ………….. category of tertiary economic activity.
4. Raw material based perspective Cotton Textile industry is a ………….. industry.
5. Capital required for establishing a large scale industry is,more than ……………

Answer:

1. Tertiary
2. Quaternary/Quinary
3. Quinary
4. Agro based
5. one crore

III. Match the following:

1. Judicial sector – Private Sector
2. TV telecasts – Non Geographical factor
3. Geographical factor – Quaternary activity
4. Capital – Raw materials
5. Bajaj Auto – Quinary activity

Answer:

1. Judicial sector — Quinary activity
2. TV telecasts – Quaternary activity
3. Geographical factor – Raw materials
4. Capital – Non Geographical factor
5. Bajaj Auto – Private Sector

IV. Distinguish the following:

8th Samacheer Kalvi Social Question 1.
Secondary economic activity and tertiary economic activity.
Answer:
1. Secondary economic activity:

• Secondary activities are those that change raw materials into usable products through processing and manufacturing.
• Bakeries that make flour into bread and factories that change metals and plastics into vehicles are examples of secondary activities.

2. Tertiary economic activity:

• Tertiary economic activities are those that provide essential services and support the industries to function. Often it is called service industries.
• It includes the transportation, finance, utilities, education, housing, medical and other services.

8th Social Science Samacheer Kalvi Question 2.
Agro based and marine based industries.
Answer:
1. Agro based industries:

• These industries use plant and animal based products as their raw materials.
• Example; Food Processing, Vegetable Oil, Cotton Textile, Dairy Products, etc.

2. Marine based Industries:

• These industries use products from the sea and oceans as raw materials.
• Example; Processed Sea Food, Fish Oil manufacturing units etc.

Samacheer Kalvi 8th Social Guide Question 3.
Large scale industries and small scale industries.
Answer:
1. Large scale industries:

• The capital required for the establishment of an industry is more than one crore the industry is called as large scale industry.
• Iron and steel, Oil refineries, Cement and Textile industries are the best examples for large scale industries.

2. Small scale Industries:

• The capital required for the establishment of an industry is less than one crore, the industry is called as small scale industry.
• Silk weaving and household industries belong to this category.

V. Answer briefly:

Samacheer Kalvi.Guru 8th Social Question 1.
Define industry.
Answer:
Industry is a process by which the raw materials are changed into finished products.

Define Industry Class 8 Question 2.
What is meant by economic activity?
Answer:
Any action that involves in the production, distribution, consumption or services is an economic activity.

Samacheer Kalvi 8th Social Question 3.
Name the major economic activities.
Answer:
The major economic activities are:

• Primary Economic Activities (e.g., Raw cotton production)
• Secondary Economic Activities (e.g., Spinning mill)
• Tertiary Economic Activities (e.g., Trade,Transport)

Samacheer Kalvi Guru 8th Social Question 4.
What are the secondary economic activities? Give some examples.
Answer:

1. Secondary activities are those that change raw materials into usable products through processing and manufacturing.
2. Bakeries that make flour into bread and factories that change metals and plastics into vehicles are examples of secondary activities.

Social Samacheer Kalvi 8th Question 5.
What is Quinary activity? Elucidate with an example.
Answer:

1. Quinary economic activities refer to the high level decision making processes by executives in industries,business, education, and government.
2. This sector include top executives or officials in the fields of science and technology, universities health care etc.
3. In our house, our parents make decisions by themselves in some situations. Similarly, the Council of Ministers take decisions to introduce various people welfare schemes in the state.
4. These two are examples of quinary activities.

Question 6.
Name the factors responsible for the location of industries.
Answer:
The locational factors of industries are grouped into.

1. Geographical factors and
2. Non-Geographical factors

1. Geographical factors include:

• Raw Materials
• Power
• Labour
• Transport
• Storage and Warehousing
• Topography
• Climate and
• Water resources.

2. Non-Geographical factors include:

• Capital
• Availability of loans and
• Government Policies / Regulations.

Question 7.
Write a short note on the following
Answer:

1. Large scale Industries
2. Small scale industries

1. Large scale Industries:
The capital required for the establishment of an industry is more than one crore the industry is called as large scale industry.
Eg : Iron & steel, Oil refineries, Cement and Textile industries etc.

2. Small scale industries:
The capital required for the establishment of an industry is less than one crore, the industry is called small scale industry.
Eg : Silk weaving and household industries.

VI. Write in detail:

Question 1.
Classify and explain the industries based on the source of raw materials.
Answer:
Industries are classified on various bases in the following ways. On the basis of raw materials.
1. Agro Based Industries:

• These industries use plant and animal based products as their raw materials.
• Example; Food Processing, Vegetable Oil, Cotton Textile, Dairy Products, etc.

2. Mineral Based Industries:

• These are the industries that use mineral ores as their raw materials.
• Iron made from iron ore is the product of mineral based industry. Cement,Machine Tools, etc. are the other examples of mineral based industries.

3. Marine Based Industries:

• These industries use products from the sea and oceans as raw materials.
• Example; Processed Sea Food, Fish Oil manufacturing units etc.

4. Forest Based Industries:

• These industries use forest products as their raw materials.
• Example; Pulp and Paper, Furniture and Some Pharmaceuticals industries, etc.

Question 2.
Explain the Geographical factors which affect the location of industries?
Answer:
Geographical factors which affect the location of industries are:
1. Raw materials:
Industries like iron and steel and sugar industries are located near the place of availability of iron ore and sugar cane respectively.

2. Power:
Power is base and essential to run the entire industry. Power is mostly generated from the conventional sources like coal, mineral oil, and water.

3. Labour:
Availability of cheap and skilled labour is another important requirement.

4. Transport:
It is needed for transporting raw materials to the industries and also for sending the finished products to the market. Availability of easy transportation always influences the location of an industry.

5. Storage and Warehousing:
Finished products should be stored at suitable storage or warehouse.

6. Topography:
The site that is selected for the establishment of an industry must be flat.

7. Climate:
Extreme climate condition is not suitable for the successful industrial growth. Cool- humid climate is ideal for cotton textile industry. Hence Coimbatore and Tiruppur are important for Cotton Textile Industries.

8. Water Resources:
Availability of water is another important factor that influences the industrial location.

Question 3.
Classify the industries through a flow chart.
Answer:

VII. Hot:

Question 1.
Find out the reasons for uneven distribution of industries in India.
Answer:

1. The distribution of Industries in India is highly uneven.
2. This is so partly on account of uneven distribution of the necessary raw materials and power resources.
3. And partly due to the contributes of enterprises, financial resources and other necessary condition in large towns.
4. Where there is good transport system, the industries flourish.
5. India’s regional growth performance has been particularly uneven.
6. Jharkhar|d, Orissa, Chattisgarh, Parts of Rajasthan, Karnataka and Tamil Nadu account for most of the reserves of metallic minerals. These are located particularly in north eastern part of Peninsula.
7. Agro based industries including Cotton, Jute and Sugar are heavily concentrated in the raw material producing areas.
8. The coastal belt of Kerala has a heavy concentration of coir, copra and fish carrying industries.

Samacheer Kalvi 8thSocial Science Geography Industries Additional Questions

I. Choose the correct answer:

Question 1.
Trade and Transport come under activities.
(a) Primary
(b) Secondary
(c) Tertiary
(d) None of the above
Answer:
(c) Tertiary

Question 2.
Information Industries belong to.
(a) Secondary activity
(b) Primary activity
(c) Quaternary activity
(d) Quinary activity
Answer:
(c) Quaternary activity

Question 3.
The backbone of the Indian economy is –
(a) Primary Sectors
(b) Service Sector
(c) Secondary Sector
(d) Name of the above
Answer:
(b) Service Sector

Question 4.
The locational factors of Industries are grouped into –
(a) Geographical factors
(b) Non – graphicaIfactors
(c) both a and b
(d) neither a nor b
Answer:
(c) both a and b

Question 5.
Cement is based industry.
(a) Agro
(b) Mineral
(c) Marine
(d) Forest
Answer:
(b) Mineral

Question 6.
In India is known as Detroit of India.
(a) Bombay
(b) Delhi
(c) Kolkatta
(d) Chennai
Answer:
(d) Chennai

II. Fill in the blanks:

1. Industry is a place of process by which the ………. are changed into products.
2. The economic strength of a country is measured by the development of ………. industries.
3. Quarrying in a ………. economic activity.
4. Education comes under ………. economic activity.
5. Industrial locations are ………. in nature.
6. Some Pharmaceutical industries come under ………. industries.
7. The industry owned and operated by an individual belongs to ………. sector.

Answer:

1. raw materials, finished
2. manufacturing
3. primary
4. Tertiary
5. complex
6. Forest based
7. private

III. Match the following:

1. Sugarcane – a) Cotton Textile Industry
2. Tea Industry – b) Require plenty of water
3. Cool humid Climate – c) Marine based Industry
4. Chemical industries – d) Raw material
5. Processed Sea food – e) Labour Intensive

Answer:

1. d
2. e
3. a
4. b
5. c

IV. Distinguish between:

Question 1.
Mineral, based industries and Forest Based Industries.
Answer:
1. Mineral based industries:

• These are the industries that use mineral ores as their raw materials.
• Eg; Iron made from iron ore, Cement Industry Machine Tools industry etc.

2. Forest based Industries:

• These industries use forest products as their raw materials.
• Eg; Pulp and Paper Industry, Furniture and Some Pharmaceuticals industries, etc.

Question 2.
Primary Economic Activity and Secondary Economic Activity.
Answer:
1. Primary Economic Activity:

• These are the economic activities which have been originated in the very beginning.
• It includes the activities such as, forestry, grazing, hunting, food gathering, fishing, agriculture, mining, and quarrying.

2. Secondary Economic Activity:

• These secondary activities are those that change raw materials into usable products through processing and manufacturing.
• Bakeries that make flour into bread and factories that change metals and plastics into vehicles.

Question 3.
Quaternary Economic Activity and Quinary Economic Activity.
Answer:
1. Quaternary Economic Activity:

• Quaternary economic activities are associated with the creation and transfer of information, including research and training. Often called information industries.
• This level has been dramatic growth as a result of advancements in technology and electronic display and transmission of information, e.g., Television.

2. Quinary Economic Activity:

• Quinary economic activities refer to the high level decision making processes by executives in industries, business, education, and government.
• This sector include top executives or officials in the fields of science and technology, universities, health care etc.

Question 4.
Private Sector Industries and Public Sector Industries.
Answer:
1. Private Sector Industries

• These type of industries are owned and operated by individuals or a group of individuals.
• Eg : Bajaj Auto, Reliance, etc.

2. Public Sector Industries:

• These type of industries are owned and operated by the Government.
• Eg: Hindustan Aeronautics Ltd (HAL), Bharat Heavy Electricals Ltd (BHEL) etc.

Question 6.
Joint Sector Industries and Co-operative Sector Industries.
Answer:
1. Joint Sector Industries:

• These types of industries are owned and operated jointly by the Government and Individuals or a group of individuals.
• Eg : Indian Oil Sky Tanking Ltd, Indian Synthetic Rubber Ltd, etc.

2. Co-operative Sector Industries:

• Industries of this kind are owned and operated by the producers or suppliers of raw materials Or workers or both.
• Eg: Anand Milk Union Limited (AMUL) is the best example of the Co-operative sector.

V. Answer briefly:

Question 1.
State the importance of the Service Sector.
Answer:
Importance of the Service Sector:

1. Service Sector is one of the largest sectors of India.
2. Currently this sector is the backbone of the Indian economy.
3. It contributes around 53% of the Indian Gross Domestic Product.

Question 2.
Explain about the availability of loans as a non geographical factor.
Answer:

1. In most cases, it is not possible to start an industry with enough capital in hand.
2. So the investors seek loan to start the industries.
3. Thus, the organizational set up which provides loan and insurance are required.

Question 3.
Why is Chennai known as Detroit of Indias?

1. Detroit city in Michigan State, USA is known as the world’s traditional automotive centre.
2. In India, Chennai is known as‘Detroit of India.
3. It has the world famous automobile industries such as GM, Ford, Hyundai and Mahindra.
4. The city accounts for 60% of the country’s automotive exports.

VI. Write in detail :

Question 1.
Explain the basic economic activities.
1. Primary economic activity :

• These are the economic activities which have been originated in the very beginning.
• It includes the activities such as, forestry, grazing, hunting, food gathering, fishing, agriculture, mining, and quarrying.

2. Secondary economic activity :

• Secondary activities are those that change raw materials into usable products through processing and manufacturing.
• Bakeries that make flour into bread and factories that change metals and plastics into vehicles are examples of secondary activities.

3. Tertiary economic activity :

• Tertiary economic activities are those that provide essential serv ices and support the industries to function.
• Often it is called service industries, which includes transportation, finance, utilities, education etc. Tertiary activity is further sub divided into Quaternary and Quinary activities.
• Quaternary activities are associated with the creation and transfer of information, including research and training.
• Quinary activity refer to the high level decision making processes by executives in industries, business, education, and government.

Students can Download Science Term 3 Chapter 7 Crop Production and Management Questions and Answers, Notes Pdf, Samacheer Kalvi 8th Science Book Solutions Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus and score more marks in your examinations.

Tamilnadu Samacheer Kalvi 8th Science Solutions Term 3 Chapter 7 Crop Production and Management

Samacheer Kalvi 8th Science Crop Production and Management Text Book Exercise

I. Choose the best answer:

8th Science Crop Production And Management Question 1.
The process of placing seeds in the soil is called as ………………..
(a) ploughing
(b) sowing
(c) crop production
(d) crop rotation
Answer:
(b) sowing

8th Standard Science Crop Production And Management Question 2.
Organism that control insects and pests of plant crops is …………………
(a) bio-pesticides
(b) bio-fertilizers
(c) earthworms
(d) neem leaves
Answer:
(a) bio-pesticides

8th Crop Production And Management Question 3.
The method in which water flows over the soil surface and allow it to infiltrate is ………………..
(a) irrigation
(b) surface irrigation
(c) springier irrigation
(d) drip irrigation
Answer:
(b) surface irrigation

Crop Production And Management Class 8 Question 4.
Effective microorganisms preparation is not used in ………………..
(a) seed treatment
(b) foliar spray
(c) soil treatment
(d) bio-predators
Answer:
(a) seed treatment

8th Standard Crop Production And Management Question 5.
Which of the following is not present in Panchakavya?
(a) cow dung
(b) cow’s urine
(c) curd
(d) sugar
Answer:
(d) sugar

II. Fill in the blanks:

1. The process of actively growing seedling from one place and planting in the main field for further growth is called ………….
2. …………. is a plant growing where it is not wanted.
3. The chemicals used for killing the weeds or inhibiting their growth are called as ………….
4. …………. seed transfer its unique characteristics to the descents.
5. …………. centers serve as the ultimate link between ICAR and farmers.
6. Several popular high yielding varieties of major crops have been developed by ………….

Answer:

1. Transplantation
2. Weed
3. herbicides
4. Heirloom seeds
5. Krishi Vigyon Kendra
6. IARi (Indian Agricultural Research Institute)

III. Match the following:

1. Bio-pesticide – (a) Neem Leaves
2. Bio-predators – (b) Bacillus thuringiensis
3. Bio-fertilizer – (c) Control white flies
4. Bio-indicators – (d) Improve soil fertility
5. Bio-repellants – (e) Quality of environment

Answer:

1. b
2. c
3. d
4. e
5. a

IV. Answer briefly:

Crop Production And Management Answers Question 1.
Define ploughing.
Answer:
Ploughing or tilling is the process of loosening and turning the soil up and down to facilitate the availability of nutrients in the root zone of that cultivating crop.

Samacheer Kalvi 8th Science Guide Question 2.
Name the methods of sowing.
Answer:
The different methods of sowing are

1. Sowing by hand
2. Seed drill
3. Dibbling

Samacheer Kalvi Guru 8th Science Question 3.
What is foliar spray?
Answer:

1. Foliar feeding is a technique of feeding plants by applying liquid fertilizer directly to their leaves.
2. Plants are able to absorb essential elements through the stomata in their leaves. Give a brief account on Krishi Vigyon Kendra.

Samacheer Kalvi Guru 8th Question 4.
Give a brief account on Krishi Vigyon Kendra.
Answer:

1. Krishi Vigyon Kendra is a farm science centre.
2. This centre serve as a ultimate link between ICAR and farmers.
3. They operate small farms to test new technologies.
4. They also provide advice to farmers about weather and pricing of crops.

Samacheer Kalvi Guru 8 Science Question 5.
What is bio-indicator? How does it help human beings?
Answer:

1. A bio-indicator or biological indicator is any species or group of species whose function or status reveals the qualitative status of the environment.
2. Biological indicators are used to document and understand changes in Earth’s living systems especially changes caused by the activities of an expanding human population.

Question 6.
What do you mean by weeding?
Answer:
The undesirable plants growing naturally with crop plants are called weeds. The removal of weeds is called weeding.

Question 7.
What is crop rotation?
Answer:
Crop rotation is planting a series of different crops in the same field following a defined order. This helps to maintain fertility of the soil.

Question 8.
What is green manure?
Answer:

1. Some plants like Sun hemp or guar are grown in the field prior to the sowing of the crop seeds.
2. These plants gradually decompose and turn into green manure which helps in ensuring the soil in nitrogen and phosphorous.
3. Application of green manure always enhance the growth and yield of the crops.

V. Answer in detail:

Question 1.
Explain the agricultural practices.
Answer:

1. Soil preparation: (LoosenIng of top soil)

• Ploughing – Process of loosening and turning the soil up and down to facilitate nutrient availability.
• levelling – Done with leveller and helps in uniform distribution of water for irrigation
• Basal Nianuring – Increase soil fertility by manuring

2. Sowing of seeds:

• Hand – Scattering of seeds by hand.
• Seed Drill – Sowing seeds by iron drills attached to a tractor.
• Dibbling – Placing seed in furrow or pits or hole by hand.

3. Adding manure and fertilisers:

• Manure is a substance added to the soil in the form of Nutrients to enhance plant growth.
• Organic Sources – Plant and animal waste
• Synthetic Sources – Urea, Super phosphate.

4. Irrigation:
Supply of water to crops:

• Traditional method – Irrigation done manually.
• Modem method – Involve two systems. Sprinkler system Drip system

5. Harvesting of crops:

• Manual harvesting – Harvested without tools. Eg – Groundnut crop, green gram, black gram, house gram.
• Mechanical method – Harvesting by instruments small sized farms Eg – Sickle.
• Machine harvesting – Used for large sized farms.

6. Threshing and Winnowing:
Process of separating the grains from their chaffs or pods.

7. Storage:

• Supply of the produce has to be stored properly.
• Grains must be free from moisture to avoid growth of microorganism.
• Need to be dried in Sun before storing.
• Collected in Gunny bags and stored in go downs.

Question 2.
Give a detailed account on irrigation.
Answer:
Irrigation:

1. The supply of water to crops at regular intervals is called irrigation.
2. Source of irrigation – Wells, tube wells, ponds, lakes, rivers, dams and canal.

Traditional Methods:

1. Irrigation is done manually.
2. Here, a farmer pulls out water from wells or canals by himself or using cattle and carries to farming fields.
3. Pumps used for lifting water from various sources.
4. Diesel, biogas, electricity and solar energy are the sources of energy needed to run these pumps.

Modern Methods:

1. It helps to overcome the problems exist in the traditional methods.
2. It also facilitates the even distribution of moisture in the field.

Sprinkler system:

1. Sprinkles water over the crop and helps in an even distribution of water.
2. This method is advisable in areas facing water scarcity.
3. Pump is connected to pipes which generate pressure and water is sprinkled through the fine nozzles of pipes.

Drip System:

1. Here, water is released drop by drop exactly at root zone using a hose or pipe.
2. This method is effective one in regions where the availability of water is less.

Question 3.
What is weed? Explain the different methods of weed control.
Answer:

Weed:
The undesirable plants may grow naturally along with the main crop, and these undesirable plants are called weeds.

Weeding:
The removal of weeds is called weeding. It is an important process because weeds compete with the crop plants for the nutrients, sunlight, water, space and other resources. It results in the undernourishment of crops and it leads to low yield.

Mechanical methods:

1. Here, weeds are destroyed physically.
2. Hand pulling or weeding with the help of weeding hole is the oldest and most efficient method for controlling weeds.

Tillage methods:

1. It is the practical methods of destroying weeds of all categories.
2. Weeds are buried in the soil and also exposed to Sun heat by deep ploughing.

Crop Rotation:
Proper rotation of crops is followed for controlling crop associated and parasitic weeds.

Summer tillage:
Deep ploughing after harvest of Rabi crop and exposing underground parts of weeds to strong sunlight during summer months is useful for destroying many annual and perennial weeds.

Biological weed control:

1. Bio agents like insects and pathogens are used to control weeds.
2. The objectives are not eradication, but reduction and regulation of the weed population.

Chemical methods:

1. Very effective in certain cases and have great scope in weed control.
2. The chemicals used for killing the weeds or inhibiting their growth are called herbicides.
3. Chemicals are mixed with water and sprayed over the crops.

Integrated weed management:

1. Integrated weed management combines different agronomic practices and herbicides use to manage weeds, so that the reliance on any one weed control technique is reduced.
2. Mechanical, biological, cultural and chemical methods are included in integrated weed managements.

Samacheer Kalvi 8th Science Crop Production and Management Additional Questions

I. Choose the correct answer:

Question 1.
…………… is a ornamental crop.
(a) Hemp
(b) Euphorbia
(c) Sorghum
(d) sesame
Answer:
(b) Euphorbia

Question 2.
Lichen is a ……………
(a) Bio-pesticide
(b) Bio-indicator
(c) Bio-predator
(d) Bio-fervilizer
Answer:
(b) Bio-indicator

Question 3.
…………… is a bio predator.
(a) Trichoderma
(b) Aphids
(C) Chrysopa spp
(d) Earthworm
Answer:
(c) Chrysopa spp

Question 4.
Neem is a good ……………
(a) Bio-fertilizer
(b) green manure
(c) insect repellant
(d) Bio predator
Answer:
(c) insect repellant

Question 5.
Royal Botanical garden is located in ……………
(a) Chennai
(b) Mumbai
(c) New Delhi is a method of
(d) Kolkatta
Answer:
(d) Kolkatta

Question 6.
…………… is a method of sowing seeds.
(a) Tillage
(b) Winnowing
(c) Weeding
(d) Dibbling
Answer:
(d) Dibbling

II. Fill in the blanks:

1. Crops sown in rainy season are called ……………
2. The summer crops are also called …………… crops.
3. …………… is an example of Rabi crop.
4. India is the largest producer of …………… in the world.
5. …………… is a fodder crop.
6. Placing a seed in a pit or furrow is called ……………
7. The process of separating the grains from their chaffs is called ……………
8. Heirloom seeds are also called …………… seeds.
9. …………… is commonly called Pusa institute.
10. The first KVK was established in 1974 in ……………
11. Vermiwash is used as a …………… for crops.
12. …………… can be used for seed treatment.
13. …………… is the main source of bio-fertilizer.

Answer:

1. Kharif
2. zaid
3. Wheat
4. Banana/ Mangoes
5. Sorghum
6. Dibbling
7. Threshing
8. Organic
9. IARI
10. Pondicherry
11. foliar spray
12. Pachgavya
13. Cyanobacteria

III. Match the following:

Question 1.

1. Paddy – (a) Fodder
2. Muskmelon – (b) Oil crop
3. Millet – (c) Zaid crop
4. Sesame – (d) Food crop

Answer:

1. d
2. c
3. a
4. b

Question 2.

1. Nostoc – (a) Pest
2. Bacillus – (b) Cyanobacteria
3. Cotton bollworm – (c) Legume
4. Rhizobium – (d) Bio-pesticide

Answer:

1. b
2. d
3. a
4. c

IV. Answer briefly:

Question 1.
How are crops classified based an seasons?
Answer:

1. Kharif crops – Sown in rainy season eg. Paddy.
2. Rabi crops – Grown in winter season eg. Wheat.
3. Zaid Crops – Grown in summer season eg. Muskmelon.

Question 2.
What is dibbling?
Answer:
It is a method of sowing seeds in which the seed material is placed in a furrow, pit or hole , spacing with a dibble and covering the same with soil.

Question 3.
Mention the difference between manure and fertilizer.
Answer:
Manure:

1. It is organic in origin
2. It does not cause pollution

Fertiliser:

1. It is synthetic in origin
2. It causes water and air pollution

Question 4.
Define threshing.
Answer:
The process of separating the grains from their chaffs or pods is called threshing.

Question 5.
Expand the following abbreviations. FCI, ICAR, KVK, IARI
Answer:

1. FCI – Food Corporation of India.
2. ICAR – Indian Council of Agricultural Research
3. KVK – Krishi Vigyon Kendra
4. IARI – Indian Agricultural Research Institute.

Question 6.
What are seed balls?
Answer:

1. Seed balls are a mixture of soil, compost and plant seeds.
2. These balls are thrown into land areas and is a step towards conserving the natural ecosystems.

Question 7.
What are heirloom seeds?
Answer:

1. An heirloom seed is the seed of plant that has been carefully cultivated and passed down through many generations.
2. Heirloom seed are harvested, dried and stored so that one can replant them in the following season.

Question 8.
What is bio-control?
Answer:

1. Bio-control or biological control is a method of controlling pests such as insects, mites, weed and plant diseases using other organisms.
2. Eg – Bio-predators, bio-pesticides, bio-repellents and bio-fertilizers.

Question 9.
What are bio-pesticides?
Answer:

1. Bio-pesticides are living organism or their derived parts which are used as bio-control agents to protect crops against insect pests.
2. Eg. Entomopathegenic viruses.

Question 10.
What are bio-fertilizer?
Answer:

1. Bio-fertilizers are organisms which bring about soil nutrient enrichment.
2. Nitrogen fixing microorganisms have the capability of converting free nitrogen into nitrogenous compounds and make the soil fertile.
3. Eg – Nostoc.

Question 11.
What is Panchgavya?
Answer:

1. A growth promoter with a combination of five products obtained from the cow, includes cow dung, cow’s urine, milk, curd and ghee.
2. It is used in seed treatment.

Question 12.
What is a seed bank?
Answer:
Seed bank is a place where seeds are stored in order to preserve genetic diversity.

Students can Download Maths Chapter 2 Measurements Ex 2.2 Questions and Answers, Notes Pdf, Samacheer Kalvi 8th Maths Book Solutions Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus and score more marks in your examinations.

Tamilnadu Samacheer Kalvi 8th Maths Solutions Term 1 Chapter 2 Measurements Ex 2.2

8th Maths Exercise 2.2 Question 1.
Find the perimeter and area of the combined figures given below, (π = \(\frac{22}{7}\))

Solution:

∴ Perimeter = Sum of all lengths of sides that form the closed boundary
P = 11 + 10 + 7 + 10m
Perimeter = 38 m
Area = Area of the rectangle – Area of semicircle

= 50.75 m² (approx)
Area of the figure = 50.75m² approx.

(ii) Perimeter = sum of outside lengths

Samacheer Kalvi 8th Maths Book Question 2.
Find the area of the shaded part of the following figures. (π = 3.14 )

Solution:
Area of the shaded part = Area of 4 quadrant circles of radius \(\frac{10}{2}\) cm
= 4 × \(\frac{1}{4}\) × πr² = 3.14 × \(\frac{10}{2} \times \frac{10}{2}\) cm²
= \(\frac{314}{4}\) cm² = 78.5cm²
Area of the shaded part = 78.5 cm²
Area of the unshaded part = Area of the square – Area of shaded part
= a² – 78.5 cm² = (10 × 10) – 78.5 cm²
= 100 – 78.5 cm² = 21.5 cm²
Area of the unshaded part = 21.5 cm² (approximately)

(ii) Area of the shaded part = Area of semicircle – Area of the triangle

∴ Area of the shaded part = 27.93 cm² (approximately)

8th Standard Maths Measurement Question 3.
Find the area of the combined figure given which is got by joining of two parallelograms.

Solution:
Area of the figure = Area of 2 parallelograms with base 8 cm and height 3 cm
= 2 × (bh) sq. units
= 2 × 8 × 3 cm² = 48 cm²
∴ Area of the given figure = 48 cm²

8th Class Maths Exercise 2.2 Question 4.
Find the area of the combined figure given, formed by joining a semicircle of diameter 6 cm with a triangle of base 6 cm and height 9 cm. (π = 3.14 )

Solution:
Area of the figure = Area of the semicircle of radius 3 cm + 2 (Area of triangle with b = 9 cm and h = 3 cm)

= 14.13 + 27 cm² = 41.13 cm²
∴ Area of the figure = 41.13 cm² (approximately)
The door mat which is in a hexagonal shape

Samacheer Kalvi 8th Books Maths Question 5.
The door mat which is in a hexagonal shape has the following measures as given in the figure. Find its area.

Solution:
Area of the doormat = Area of 2 trapezium
Height of the trapezium h = \(\frac{70}{2}\) cm;
a = 90 cm; b = 70 cm
∴ Area of the trapezium
= \(\frac{1}{2}\)h (a + b) sq. units
Area of the door mat
= 2 × \(\frac{1}{2}\) × 35 (90 + 70) cm²
= 35 × 160 cm² = 5600 cm²
∴ Area of the door mat = 5600 cm²

Samacheer Kalvi 8th Maths Question 6.
Find the area of an invitation card which has two semicircles attached to a rectangle as in the figure given. (π = \(\frac{22}{7}\))

Solution:
Area of the card = Area of the rectangle + area of 2 semicircles
Length of the rectangle l = 30 cm
Breadth b = 21 cm
Radius of the semicircle = \(\frac{21}{27}\)
∴ Area of the card
= (l × b) + (2 × \(\frac{1}{2}\) πr²) sq. units
= 30 × 21 + \(\frac{22}{7} \times \frac{21}{2} \times \frac{21}{2}\) cm² = 630 + 346.5
= 976.5 cm² (approximately)
∴ Area of the Invitation card = 976.5 cm²

8th Maths Book Samacheer Kalvi Question 7.
Find the area of the combined figure given, which has two triangles attached to a rectangle.

Solution:
Area of the combined shape = Area of the rectangle + Area of 2 triangles
Length of the rectangle l = 10 cm
Breadth b = 8 cm
Base of the triangle base = 8 cm
Height h = 6 cm
∴ Area of the shape = (l × b) + (2 × \(\frac{1}{2}\) × base × h) cm²
= (10 × 8) + (8 × 6) cm² = 80 + 48 cm² = 128 cm²
Area of the given shape = 128 cm²

Samacheer Kalvi 8th Standard Maths Question 8.
A rocket drawing has the measures as given in the figure. Find its area.

Solution:
Area = Area of a rectangle + Area of a triangle + Area of a trapezium
For rectangle length l = 120 – 20 – 20 cm = 80 cm
Breadth b = 30 cm
For the triangle base = 30 cm
Height = 20 cm
For the trapezium height h = 20 cm
Parallel sided a = 50 cm
b = 30 cm
∴ Area of the figure = (l × b) + (\(\frac{1}{2}\) × base × height) + \(\frac{1}{2}\) × h × (a + b) sq. units
= (80 × 30) + ( \(\frac{1}{2}\) × 30 × 20) + \(\frac{1}{2}\) × 20 × (50 + 30) cm²
= 2400 + 300 + 800 cm² = 3500 cm²
Area of the figure = 3500 cm²

Samacheer Kalvi 8 Maths Book Question 9.
Find the area of the glass painting which has a triangle on a square as given in the figure.

Solution:
Area of the glass painting = Area of the square + Area of the triangle
Side of the square a = 30 cm
Base of the triangle b = 30 cm
Height of the triangle h = 8 cm
∴ Area of the painting = (a)² + (\(\frac{1}{2}\) bh) sq. units
= (30 × 30) + (\(\frac{1}{2}\) × 30 × 8) cm² = 900 + 120 cm²
= 1020 cm²
Area of the glass painting = 1020 cm²

8th Standard Maths Samacheer Kalvi Question 10.
Find the area of the irregular polygon shaped fields given below.

Solution:
(i) Area of the irregular field = Area of ∆AHF + Area of trapezium FHIE + Area of triangle EID + Area of ∆JDC + Area of rectangle BGJC + Area of ∆AGB

(ii) Area of the field = Area of trapezium FBCH + Area of ∆DHC + Area of ∆EGD + Area of ∆EGA + Area of ∆BFA