Class 7 Science Chapter 12 NCERT Solutions Hinglish mein: Earth, Moon, and the Sun

Class 7 Science textbook Curiosity (Reprint 2026-27) ke Chapter 12, Earth, Moon, and the Sun, ke har sawaal ka jawab: paath ke sawaal, sample observations ke saath Activities 12.1–12.4, “Let Us Enhance Our Learning” ke saare 12 sawaal aur teeno exploratory projects. Page numbers book se milte hain (pages 169–186). Chhote notes: Chapter 12 ke notes.

Rashmika ka sawaal (page 169)

Kya Sun aasmaan mein chalta hai, ya Earth chalti hai? Earth chalti hai. Wo apni axis pe West se East rotate karti hai, aur is ghoomti Earth se Sun sirf East se West aasmaan paar karta dikhta hai. Rashmika ne jo parchhaaiyan dekhi, wo bhi isi wajah se badalti hain. Subah Sun East mein neeche hota hai, isliye parchhaaiyan lambi hoti hain; dopahar ke aas paas wo upar hota hai, isliye parchhaaiyan chhoti; shaam ko wo West mein neeche hota hai aur parchhaaiyan phir lambi ho jaati hain.

Earth ka rotation (pages 170–175)

Activity 12.1: merry-go-round pe kya aas paas ki cheezein chalti dikhti hain? Haan. Jab merry-go-round anti-clockwise ghoomta hai, aas paas ki cheezein ulti taraf, clockwise, ghoomti dikhti hain. Jis ped ko tum dekhte ho wo har samay nazar mein nahi rehta: wo baayein se aata hai aur daayein nazar se ojhal ho jaata hai.

Sun chal raha hai, ya Earth ghoom rahi hai? Earth ghoom rahi hai. Jaise merry-go-round pe ped chalte dikhte hain, waise hi ghoomti Earth se dekhne ki wajah se Sun chalta dikhta hai.

Activity 12.2: poorvi India pe pehle roshni pade, iske liye globe ko kis taraf ghumaana hoga? West se East, uski North–South axis pe. Is taraf ghumaane pe tumhari nishaan lagi jagah poora chakra poora karti hai: roshni mein aate hi sunrise, din, andhere mein jaate hi sunset, aur raat.

Ek rotation ke dauraan Equator pe khade hokar tum kya dekhoge? Kya Fig. 12.6 ki ladki jaisa? Haan, waisa hi. Uttar ki taraf munh karke tum subah Sun ko apne daayein, East mein, ugta dekhoge; dopahar ke aas paas wo sir ke upar hoga; shaam ko wo tumhare baayein, West mein, doobega. Phir raat hogi aur taare nikal aayenge.

Earth ghoomti hai, to kya taare bhi chalte nahi dikhne chahiye? Haan. Taare bhi East mein ugte aur West mein doobte dikhte hain, jaise Activity 12.3 dikhati hai.

Activity 12.3: kya Big Dipper Pole Star ke chaaron taraf ghoomta dikhta hai? Haan. April ki ek raat uttar India se sample observations: 8 pm pe Big Dipper north-east mein neeche hai; 10 pm tak wo upar chadh kar mud gaya hai; aadhi raat tak wo Pole Star ke kaafi upar hai. Wo har 2 ghante mein lagbhag 30° Pole Star ke chaaron taraf anti-clockwise ghoomta hai, jabki Pole Star lagbhag nahi hilta, kyunki Earth ki axis lagbhag usi ki taraf hai.

Earth ka revolution (pages 175–179)

Saal bhar mein raat ke aasmaan mein alag taare kyun dikhte hain? Kyunki Earth Sun ka chakkar lagaati hai. Earth ka raat waala hissa hamesha Sun se door hota hai, isliye orbit pe aage badhte hue wo antariksh ke alag hisse ki taraf dekhta hai. Isliye sunset pe ugne waale taare mahine dar mahine badalte hain, aur wahi taare ek saal baad laut aate hain.

Kya seasons ka chakra Earth ke revolution se juda hai? Garmi ke din lambe kyun hote hain? Haan. Jhuki axis ke saath Earth ke chakkar lagaane pe har hemisphere baari baari Sun ki taraf jhukta hai. Sun ki taraf jhuke hemisphere ko zyaada ghani dhoop milti hai aur wo har rotation ka aadhe se zyaada hissa roshni mein bitaata hai, isliye wahan din 12 ghante se lambe hote hain aur garmi hoti hai.

Grahan (pages 179–183)

Kya Mercury ya Venus Sun ki roshni rok sakte hain? Nahi. Dono Moon se bade hain, par hamse bahut door hain, isliye Sun ke saamne bahut chhote dikhte hain. Sun ke aage se guzarta Venus sirf ek chhota kaala dot dikhta hai, Transit of Venus. Sirf Moon Sun ko poora rok sakta hai.

Activity 12.4: kya tumhara angootha 5 metre door dost ka sir dhak sakta hai? Haan. Angootha sir se bahut chhota hai par aankh ke bahut paas hai, isliye dono lagbhag ek jitne dikhte hain. Koi cheez kitni badi dikhti hai, ye uske asli size aur doori dono pe nirbhar hai.

Let Us Enhance Our Learning (pages 184–186)

1. Fig. 12.17 mein ek rotation ke dauraan North Pole aur South Pole ko kitne ghante dhoop milti hai? Figure mein North Pole roshni se door jhuka hai aur poore chakkar mein andhere aadhe mein hi rehta hai, isliye use 0 ghante dhoop milti hai. South Pole roshan aadhe ki taraf jhuka hai aur wahin rehta hai, isliye use 24 ghante dhoop milti hai. Ye December ke aas paas ki Earth hai.

2. Khaali jagah bharo. (i) Taare East mein ugte hain aur West mein doobte hain. (ii) Din aur raat Earth ke rotation se hote hain. (iii) Jab Moon hamari nazar se Sun ko poora dhak leta hai, to use total surya grahan kehte hain.

3. True ya False.

• (i) False. Chandra grahan tab hota hai jab Earth Sun aur Moon ke beech aati hai.
• (ii) False. Earth West se East ghoomti hai, isliye poorv ki jagahon ko pehle dhoop milti hai. Jharkhand Gujarat se poorv mein hai, isliye sunrise Jharkhand mein pehle hota hai.
• (iii) True. Chennai Northern Hemisphere mein hai, isliye uska sabse lamba din summer solstice, lagbhag 21 June, ko hota hai.
• (iv) False. Surya grahan ko kabhi nange aankh se mat dekho; isse aankhein kharaab ho sakti hain.
• (v) True.
• (vi) False. Din aur raat Earth ke rotation se hote hain, revolution se nahi.

4. Padmashree ne kal raat 8 baje Orion ko lagbhag sir ke upar dekha. Aaj wo use sir ke upar kab dekhegi? Lagbhag usi samay, 8 baje ke aas paas. Theek theek kahein to lagbhag 4 minute pehle, 7:56 pm ke aas paas, kyunki Earth taaron ke hisaab se 24 ghante mein nahi, balki lagbhag 23 ghante 56 minute mein ek baar ghoomti hai, jaisa Aryabhata ne nikaala tha.

5. Nandhini ne 21 June ko aadhi raat ko taaron ka ek samooh ugta dekha. Agle saal wo unhe aadhi raat ko kab ugta dekhegi? Agle saal 21 June ko. Ek poore revolution, lagbhag 365 din, ke baad Earth apni orbit ke usi bindu pe laut aati hai, isliye aadhi raat ka aasmaan phir waisa hi dikhta hai.

6. Jab India mein din hota hai to USA mein raat kyun hoti hai? Earth ke rotation ki wajah se. India aur USA Earth ki lagbhag ulti taraf hain. Jab India Sun ki taraf hota hai aur wahan din hota hai, USA Sun se door hota hai aur wahan raat hoti hai. (Extra) USA ke hisse ke hisaab se samay ka fark lagbhag 9½ se 12½ ghante hai.

7. Kaun laaparvaah tha? Adithya (iii), jisne Sun ko seedhe dekha. Isse aankhein kharaab ho sakti hain aur andhapan bhi ho sakta hai. Goggles, projected image aur planetarium ka programme teeno surakshit hain.

8. Fig. 12.18 ke gole bharo. Surya grahan: Sun, Moon, Earth (beech mein Moon). Chandra grahan: Sun, Earth, Moon (beech mein Earth).

9. Moon Sun se bahut chhota hai. Phir bhi wo Sun ko poora kaise dhak leta hai? Koi cheez kitni badi dikhti hai, ye uske size aur doori pe nirbhar hai. Moon Sun se bahut chhota hai par hamare bahut paas bhi hai, isliye hamare aasmaan mein dono lagbhag ek jitne dikhte hain, aur Moon poore Sun ko dhak sakta hai, jaise angootha sir ko. (Extra) Sun Moon se lagbhag 400 guna chauda hai, aur lagbhag 400 guna door bhi.

10. December mein Australia ke match: sardi ke kapde ya garmi ke? Garmi ke kapde. Australia Southern Hemisphere mein hai, jahan seasons India ke ulat hote hain: wahan December mein garmi hoti hai.

11. Chandra grahan Earth ke bade hisse se kyun dikhta hai, par total surya grahan sirf chhote hisse se? Chandra grahan mein Earth ki parchhaai khud Moon ko dhakti hai, isliye Earth ke raat waale hisse mein jo bhi Moon dekh sakta hai, use wo kaala hota dikhta hai, yaani lagbhag aadhi Earth ko ek saath. Surya grahan mein Moon chhota hai, isliye uski sabse gehri parchhaai Earth ke sirf ek chhote hisse ko dhakti hai, aur sirf wahan ke log total grahan dekhte hain; aas paas ke bade hisse mein partial grahan dikhta hai.

12. Agar Earth ki axis jhuki na hoti to seasons ka kya hota? Lagbhag koi season nahi hota. Har jagah saal bhar lagbhag 12 ghante din aur 12 ghante raat hoti, aur dhoop ki taakat lagbhag ek jaisi rehti, isliye har jagah saal bhar lagbhag ek jaisa mausam rehta. Equator ke paas ki jagahein garam aur dhruvon ke paas ki thandi hi rehti.

Exploratory projects (page 186)

1. Lamp ke chaaron taraf jhuka globe. Globe ko lamp ke chaaron taraf ghumaate samay uska jhukaav ek hi disha mein rakho. (i) Jahan North Pole lamp ki taraf jhuka ho, wahan Northern Hemisphere ka zyaada hissa roshan hota hai; jahan door jhuka ho, wahan Southern Hemisphere ka; beech ki do jagahon pe dono barabar roshan hote hain. (ii) Globe ghumaane pe roshan hemisphere mein din raat se lambe, doosre mein chhote, aur Equator pe hamesha barabar hote hain. (iii) Beech ki jagahon pe har jagah din aur raat barabar hote hain, jaise equinox, aur lamp ki taraf jhuka dhruv poore chakkar mein roshan rehta hai.

2. 14.7 cm aur 15.2 cm ke do gole. 1 cm = 1 crore km lene pe ye Sun se Earth ki sabse kam aur sabse zyaada doori dikhate hain, 147 million km aur 152 million km. Gole lagbhag ek doosre pe chadhe hain: fark sirf 50 lakh km, lagbhag 3%, hai. Orbit lagbhag gol hai, aur ye chhota badlaav seasons nahi la sakta; Earth to January mein Sun ke sabse paas hoti hai.

3. Zyaada jhukaav, zyaada tez seasons? Uranus. Haan: zyaada jhukaav se har hemisphere garmi mein Sun ki taraf aur zyaada jhukta aur sardi mein aur door, jisse garmi zyaada garam, sardi zyaada thandi, aur zyaada jagahon pe 24 ghante ka din ya raat hoti. (Extra) Uranus lagbhag 98° jhuka hai, yaani lagbhag karvat leke ghoomta hai. Uska ek saal lagbhag 84 Earth saal ka hai, isliye har dhruv ko lagbhag 42 saal dhoop aur phir 42 saal andhera milta hai. Inhi tathyon se apna lekh likho.