56. At a given volume and temperature, the pressure of a gas

1. 1. Varies inversely as its mass

   
   
   

   2. Varies inversely as the square of its mass

   
   
   

   3. Varies linearly as its mass

   
   
   

   4. Is independent of its mass

   
   
   

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   N/A

   Correct Option: C

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57. Water is used in hot water bags because

1. 1. It is easily obrained

   
   
   

   2. It is cheaper and is not harmful

   
   
   

   3. It has high specific heat

   
   
   

   4. It is easy to heat water

   
   
   

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   N/A

   Correct Option: C

   N/A

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58. The temperature of water at the bottom of a waterfall is higher than that at the top because

1. 1. Water at the bottom has greater potential energy

   
   
   

   2. The surface at the bottom provides heat

   
   
   

   3. Kinetic energy of falling water is converted into heat

   
   
   

   4. Falling water absorbs heat from the surroundings

   
   
   

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   N/A

   Correct Option: C

   N/A

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59. 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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60. 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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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: C

   N/A

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