11. The energy that can harness heat stored below the earth's surface is known as

1. 1. Thermal energy

   
   
   

   2. Nuclear energy

   
   
   

   3. Tidal energy

   
   
   

   4. Geo-thermal energy

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: D

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12. Heat energy of an object is

1. 1. The average energy of the molecules of the object

   
   
   

   2. The total energy of the molecules of the object

   
   
   

   3. The average velocity of the molecules of the objects

   
   
   

   4. The average potential energy of the molecules of the object

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: B

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13. In a pressure cooker the cooking is fast because

1. 1. The boiling point of water is raised by the increased pressure inside the cooker

   
   
   

   2. The boiling point of water is lowered by the increased pressure

   
   
   

   3. More steam is available to cook the food at 1000°C

   
   
   

   4. None of the above

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: A

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14. When an ideal gas under goes an isothermal expansion, the pressure of the gas in the enclosure falls. This is due to

1. 1. Decreased in the change of momentum per collision

   
   
   

   2. Decrease in the frequency of collision

   
   
   

   3. Decrease in the frequency of collision and the change of momentum per collision

   
   
   

   4. Decrease in neither the frequency of collision nor the change of momentum per collision

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: B

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15. Which of the following statement (s) is (are) true about thermal radiations?
    (i) Thermal radiation are electromagnetic waves
    (ii) All bodies emit thermal radiations at all temperature
    (iii) Thermal radiations are reflected from mirror
    (iv) Thermal radiations of all wavelengths travel in free space with same velocity
    Choose the correct answer

1. 1. (i), (ii) and (iii)

   
   
   

   2. (ii), (iii) and (iv)

   
   
   

   3. (iii) and (iv)

   
   
   

   4. All of them

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: D

   N/A

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