61. Clothes keep us warm in winter because they

1. 1. Supply heat

   
   
   

   2. Do not radiate heat

   
   
   

   3. Prevent air from contacting the body

   
   
   

   4. Prevent the heat of the body from escaping

   
   
   

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   N/A

   Correct Option: D

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62. Water equivalent is equal to the product of

1. 1. Mass and Avogadro number

   
   
   

   2. Mass and gas counstant

   
   
   

   3. Mass and specific heat

   
   
   

   4. Latent heat and volume of water

   
   
   

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   N/A

   Correct Option: C

   N/A

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63. A liquid boils at a temperature at which its saturated vapour pressure becomes

1. 1. Equal to the atmospheric pressure

   
   
   

   2. Twice the atmospheric pressure

   
   
   

   3. Half the atmospheric pressure

   
   
   

   4. None of the above

   
   
   

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   N/A

   Correct Option: A

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64. The temperature of boiling water in a steam engine may be high because

1. 1. There are dissolved substances in water

   
   
   

   2. There is low pressure inside the boiler

   
   
   

   3. There is high pressure inside the boiler

   
   
   

   4. The fire is at very high temperature

   
   
   

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   N/A

   Correct Option: C

   N/A

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65. The critical temperature of a gas is the temperature

1. 1. At which Boyle's law is strictly obeyed

   
   
   

   2. At which the gas liquefies at a pressure of one atmosphere

   
   
   

   3. Above which the gas cannot be liquefied

   
   
   

   4. Below which the gas cannot be liquefied

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: C

   N/A

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