81. A real gas can be liquefied by the application of pressure when its temperature is

1. 1. Above the room temperature

   
   
   

   2. Above the inversion temperature

   
   
   

   3. At the Boyle temperature

   
   
   

   4. At the critical temperature

   
   
   

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   N/A

   Correct Option: D

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82. The product of the pressure and volume of an ideal gas is

1. 1. A constant

   
   
   

   2. Approximately equal to the universal gas constant

   
   
   

   3. directly proportional to its temperature

   
   
   

   4. Inversely proportional to its temperature

   
   
   

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   N/A

   Correct Option: C

   N/A

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83. Consider the following statements
    1. Steam at 100°C contain same amount of heat
    2. Latent heat of fusion of ice is equal to the latent heat of vaporization of water
    3. In air-conditioner, coils and is rejected out at the condenser coils
    Which of these statements is / are correct ?

1. 1. 1 and 2

   
   
   

   2. 2 and 3

   
   
   

   3. Only 2

   
   
   

   4. Only 3

   
   
   

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   N/A

   Correct Option: D

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84. According to Newton's law of cooling, the rate of cooling of a body is proportional to the

1. 1. Temperature of the body

   
   
   

   2. Temperature of the surrounding

   
   
   

   3. difference of the temperature of the body and its surroundings

   
   
   

   4. None of the above

   
   
   

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   N/A

   Correct Option: C

   N/A

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85. A polished metal plate with rough black spot on it is heated to about 2000 K and quickly taken to a dark room. Then the spot

1. 1. Will appear brighter than the plate

   
   
   

   2. Will appear darker than the plate

   
   
   

   3. And the plate will appear equally bright

   
   
   

   4. None of the above

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: A

   N/A

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