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Q1. Electricity is produced through dry cell from
_________ के माध्यम से ड्राई सेल से बिजली का उत्पादन किया जाता है?
(a) chemical energy / रासायनिक ऊर्जा
(b) thermal energy / ऊष्मीय ऊर्जा
(c) mechanical energy/ यांत्रिक ऊर्जा
(d) nuclear energy / परमाणु ऊर्जा
Q2. Which of the following items is used in the household wirings to prevent accidental fire in case of short circuit?
शॉर्ट सर्किट के मामले में आकस्मिक आग को रोकने के लिए घरेलू सामानों में निम्नलिखित में से किस वस्तु का उपयोग किया जाता है?
(a) Insulated wire / इंसुलेटेड तार
(b) Plastic switches/ प्लास्टिक स्विच
(c) Non-metallic coatings on conducting wires / तारों के संचालन पर गैर-धातु कोटिंग
(d) Electric fuse / इलेक्ट्रिक फ्यूज
Q3. When three resistors each having resistance, ‘r’ are connected in parallel, their resultant resistance is x. If these three resistances are connected in series, the total resistance will be
जब ‘r’ प्रतिरोध वाले तीन प्रतिरोधक समानांतर में जोड़े जाते हैं, तो उनका परिणामी प्रतिरोध x होता है। यदि यह तीन प्रतिरोधों को श्रेणी में जोड़ा जाता है, तो कुल प्रतिरोध क्या होगा?
(a) 3 x
(b) 12x
(c) 9 x
(d) 3/x
Q4. Suppose the force of gravitation between two bodies of equal masses is F. If each mass is doubled keeping the distance of separation between them unchanged, the force would become
मान लीजिए कि समान द्रव्यमान वाले दो निकायों के बीच गुरुत्वाकर्षण बल F है। यदि प्रत्येक द्रव्यमान को उनके बीच के पृथक्करण की दूरी को अपरिवर्तित रखते हुए दोगुना कर दिया जाए, तो बल _____ हो जाएगा
(a) F
(b) 2F
(c) 4F
(d) 1/4F
एक साधारण सर्किट में 12 V की बैटरी और 24 ओम प्रतिरोध वाला बल्ब है। जब आप स्विच को चालू करते हैं, तो सर्किट में जुड़ा एमीटर
(a) 0.5 A
(b) 2 A
(c) 4 A
(d) 5 A
Q6. Three resistors with magnitudes 2, 4 and 8 ohm are connected in parallel. The equivalent resistance of the system would be
परिमाण 2, 4 और 8 ओम के साथ तीन प्रतिरोध समानांतर में जुड़े हुए हैं। प्रणाली का समतुल्य प्रतिरोध होगा
(a) less than 2 ohm / 2 ओम से कम
(b) more than 2 ohm but less than 4 ohm / 2 ओम से अधिक लेकिन 4 ओम से कम
(c) 4 ohm/4 ओम
(d) 14 ohm/ 14 ओम
_________ के माध्यम से ड्राई सेल से बिजली का उत्पादन किया जाता है?
(a) chemical energy / रासायनिक ऊर्जा
(b) thermal energy / ऊष्मीय ऊर्जा
(c) mechanical energy/ यांत्रिक ऊर्जा
(d) nuclear energy / परमाणु ऊर्जा
Show Answer
Ans.(a)
Sol. Electricity is produced through dry cell from chemical energy. The cell from which electric energy is derived by irreversible chemical action are called primary cells. The primary cell is capable of providing an EMF when its constituent’s two electrodes and a suitable electrolyte are assembled together. The three main primary cells are the Daniel cell, the Leclanche cell, and the dry cell. None of these cells can be recharged electrically.
Sol. Electricity is produced through dry cell from chemical energy. The cell from which electric energy is derived by irreversible chemical action are called primary cells. The primary cell is capable of providing an EMF when its constituent’s two electrodes and a suitable electrolyte are assembled together. The three main primary cells are the Daniel cell, the Leclanche cell, and the dry cell. None of these cells can be recharged electrically.
Q2. Which of the following items is used in the household wirings to prevent accidental fire in case of short circuit?
शॉर्ट सर्किट के मामले में आकस्मिक आग को रोकने के लिए घरेलू सामानों में निम्नलिखित में से किस वस्तु का उपयोग किया जाता है?
(a) Insulated wire / इंसुलेटेड तार
(b) Plastic switches/ प्लास्टिक स्विच
(c) Non-metallic coatings on conducting wires / तारों के संचालन पर गैर-धातु कोटिंग
(d) Electric fuse / इलेक्ट्रिक फ्यूज
Show Answer
Ans.(d)
Sol. Electric fuse in electric circuit is a device which is used to interrupt any type of accidental fire due to short circuit.
Sol. Electric fuse in electric circuit is a device which is used to interrupt any type of accidental fire due to short circuit.
Q3. When three resistors each having resistance, ‘r’ are connected in parallel, their resultant resistance is x. If these three resistances are connected in series, the total resistance will be
जब ‘r’ प्रतिरोध वाले तीन प्रतिरोधक समानांतर में जोड़े जाते हैं, तो उनका परिणामी प्रतिरोध x होता है। यदि यह तीन प्रतिरोधों को श्रेणी में जोड़ा जाता है, तो कुल प्रतिरोध क्या होगा?
(a) 3 x
(b) 12x
(c) 9 x
(d) 3/x
Show Answer
Ans.(c)
Sol. When three resistors each having resistance, ‘r’ are connected in parallel, their resultant resistance is x hence,
1/x=3/r
r=3X,
Again ,
If these three resistances are connected in series,
Total resistance =3r=3x3X=9X.
Sol. When three resistors each having resistance, ‘r’ are connected in parallel, their resultant resistance is x hence,
1/x=3/r
r=3X,
Again ,
If these three resistances are connected in series,
Total resistance =3r=3x3X=9X.
Q4. Suppose the force of gravitation between two bodies of equal masses is F. If each mass is doubled keeping the distance of separation between them unchanged, the force would become
मान लीजिए कि समान द्रव्यमान वाले दो निकायों के बीच गुरुत्वाकर्षण बल F है। यदि प्रत्येक द्रव्यमान को उनके बीच के पृथक्करण की दूरी को अपरिवर्तित रखते हुए दोगुना कर दिया जाए, तो बल _____ हो जाएगा
(a) F
(b) 2F
(c) 4F
(d) 1/4F
Show Answer
Ans.(c)
Sol. According to the universal law of gravitation, everybody in the universe attract other body with a force which is directly proportional to the product of their masses and inversely proportional to the square of the distance between them. Therefore mass is doubled then the force acting between them F, will become 4F.
Q5. A simple circuit contains a 12 V battery and a bulb having 24 ohm resistance. When you turn on the switch, the ammeter connected in the circuit would read Sol. According to the universal law of gravitation, everybody in the universe attract other body with a force which is directly proportional to the product of their masses and inversely proportional to the square of the distance between them. Therefore mass is doubled then the force acting between them F, will become 4F.
एक साधारण सर्किट में 12 V की बैटरी और 24 ओम प्रतिरोध वाला बल्ब है। जब आप स्विच को चालू करते हैं, तो सर्किट में जुड़ा एमीटर
(a) 0.5 A
(b) 2 A
(c) 4 A
(d) 5 A
Show Answer
Ans.(a)
Sol. i = V/R = 12/24 = 0.5 A
Sol. i = V/R = 12/24 = 0.5 A
Q6. Three resistors with magnitudes 2, 4 and 8 ohm are connected in parallel. The equivalent resistance of the system would be
परिमाण 2, 4 और 8 ओम के साथ तीन प्रतिरोध समानांतर में जुड़े हुए हैं। प्रणाली का समतुल्य प्रतिरोध होगा
(a) less than 2 ohm / 2 ओम से कम
(b) more than 2 ohm but less than 4 ohm / 2 ओम से अधिक लेकिन 4 ओम से कम
(c) 4 ohm/4 ओम
(d) 14 ohm/ 14 ओम
Show Answer
Ans.(a)
Sol. 1/R=1/R_1 +1/R_2 +1/R_3
=1/2+1/4+1/8
=7/8
R = 8/7, it is more than one and less than 2.
Sol. 1/R=1/R_1 +1/R_2 +1/R_3
=1/2+1/4+1/8
=7/8
R = 8/7, it is more than one and less than 2.
Q7. Consider the following circuit:
The equivalent resistance of the circuit when there resistance 2,4 and 6 ohm are connected in parallel to each other are connected to series 8 ohm. Find the equivalent resister in circuit ?
निम्नलिखित सर्किट पर विचार करें:
सर्किट के समतुल्य प्रतिरोध जब 2,4 और 6 ओम प्रतिरोध एक दूसरे के समानांतर में जुड़े होते हैं, तो श्रेणी 8 ओम से जुड़े होते हैं। सर्किट में बराबर रिसिस्टर का पता लगाएं?
(a) 12 Ω
(b) 8 11/12 Ω
(c) 9 1/11 Ω
(d) 24/25 Ω
Show Answer
Ans.(c)
Sol. 1/R=1/R_1 +1/R_2 +1/R_3
=1/2+1/4+1/6
=11/12
R = 12/11
Total resistance = 12/11+8=100/11=9 1/11 ohm.
Sol. 1/R=1/R_1 +1/R_2 +1/R_3
=1/2+1/4+1/6
=11/12
R = 12/11
Total resistance = 12/11+8=100/11=9 1/11 ohm.
Q8. A man weighing 70 kg is coming down in a lift. If the cable of the lift breaks suddenly, the weight of the man would become
एक लिफ्ट में 70 किलो वजन का आदमी नीचे आ रहा है। लिफ्ट का केबल अचानक टूट जाता तो आदमी का वजन कितना हो जाता है?
(a) 70 kg /किलो
(b) 35 kg / किलो
(c) 140 kg / किलो
(d) zero /शून्य
Show Answer
Ans.(d)
Sol. If the cable of the lift breaks suddenly the weight of the man would become zero because the system would all begin to accelerate downward due to the force of gravity. All objects in the freefall accelerate downward with the same magnitude.
Sol. If the cable of the lift breaks suddenly the weight of the man would become zero because the system would all begin to accelerate downward due to the force of gravity. All objects in the freefall accelerate downward with the same magnitude.
Q9. A given conductor carrying a current of 1 A produces an amount of heat equal to 2000 J. If the current through the conductor is doubled, the amount of heat produced will be
एक दिया गया कंडक्टर 1 A का करंट ले जाता है जो 2000 J के बराबर ऊष्मा की मात्रा पैदा करता है। यदि कंडक्टर के माध्यम से करंट को दोगुना किया जाता है, तो उत्पादित ऊष्मा की मात्रा होगी
(a) 2000 J
(b) 4000 J
(c) 8000 J
(d) 1000 J
Show Answer
Ans.(c)
Sol. Heat produced by wire , H= I2RT
2000=12RT(I=1given)
RT=2000
When I=2
Then Heat (H)= I2RT
H = 22RT
= 4RT
=4x2000
=8000J
Sol. Heat produced by wire , H= I2RT
2000=12RT(I=1given)
RT=2000
When I=2
Then Heat (H)= I2RT
H = 22RT
= 4RT
=4x2000
=8000J
Q10. Two long wires each carrying a d.c. current in the same direction are placed close to each other. Which one of the following statements is correct?
दो लम्बे तार जिसमें एक ही दिशा में d.c. करंट जा रहा है एक दुसरे के करीब राखी जाती है.
निम्नलिखित में से कौन सा कथन सत्य है?
(a) The wires will attract each other / तार एक दूसरे को आकर्षित करेंगे
(b) The wires will repel each other / तार एक दूसरे को विकर्षण करेंगे
(c) There will be no force between the wires / तारों के बीच कोई बल नहीं होगा
(d) There will be a force between the wires only at the moment when the current is switched ON or OFF / चालू या बंद चालू होने पर ही तारों के बीच एक बल होगा
Show Answer
Ans.(a)
Sol. When wire carrying d. c . current in the same direction are placed close to each other, the wire will attract each other
Sol. When wire carrying d. c . current in the same direction are placed close to each other, the wire will attract each other
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