86. The pressure of the earth's atmosphere at sea level is due to the

1. 1. Fact that most living things constantly breathe air

   
   
   

   2. Gravitational attraction of the earth for the atmosphere

   
   
   

   3. Evaporation of water from the seas and oceans

   
   
   

   4. Heating of the atmosphere by the sun

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: B

   N/A

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87. The relay satellite transmits the television programme continuously from one part of the world to another because its

1. 1. Period is greater than the period of rotation of the earth about its axis

   
   
   

   2. Period is less than the period of rotation of the earth about its axis

   
   
   

   3. Period is less than the period of rotation of the earth about its axis

   
   
   

   4. Mass is less than the mass of the earth

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: C

   N/A

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88. A bullet hits and gets embedded in a solid block resting on a horizontal frictionless table. What is conserved?

1. 1. Momentum and KE

   
   
   

   2. Momentum

   
   
   

   3. KE

   
   
   

   4. Neither momentum nor KE

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: B

   N/A

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89. A rocket works on the principle of conservation of

1. 1. Mass

   
   
   

   2. Linear momentum

   
   
   

   3. Energy

   
   
   

   4. Angular momentum

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: B

   N/A

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90. The plane of the orbit of an earth satellite

1. 1. Passes through the centre of the earth

   
   
   

   2. Does not pass through the centre of the earth

   
   
   

   3. May or may not pass through the centre of the earth

   
   
   

   4. Oscillates about the centre of the earth

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: A

   N/A

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