21. An ideal liquid flows through a horizontal tube of variable diameter. The pressure is lowest where the

1. 1. Velocity is highest

   
   
   

   2. Velocity is lowest

   
   
   

   3. Diameter is largest

   
   
   

   4. None of these

   
   
   

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   N/A

   Correct Option: A

   N/A

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22. When the external torque on a system is zero, there will be conservation of its

1. 1. Linear momentum

   
   
   

   2. Angular momentum

   
   
   

   3. Total energy

   
   
   

   4. None of these

   
   
   

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   N/A

   Correct Option: C

   N/A

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23. A particle revolves round a circular path with a constant speed the acceleration of the particle is

1. 1. Along the circumference of the circle

   
   
   

   2. Along the tangent

   
   
   

   3. Along the radius

   
   
   

   4. Zero

   
   
   

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   N/A

   Correct Option: C

   N/A

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24. The minimum number of non-zero non-collinear vectors required to produce a zero vector is

1. 1. 3

   
   
   

   2. 2

   
   
   

   3. 4

   
   
   

   4. 1

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: A

   N/A

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25. A pendulum clock is set to give correct time at the sea level. This clock is moved to a hill station at an altitude of 2500 m above the sea level. In order to keep correct time on the hill station, the length of the pendulum

1. 1. Has to be reduced

   
   
   

   2. Has to be increased

   
   
   

   3. Needs no adjustment

   
   
   

   4. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: A

   N/A

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