1 ) A body of mass 5 kg is moving with a momentum of 10 kg m / s . A force of 0.2 N acts on it in the direction of motion of body for 10 secs . The increase in its kinetic energy is ?

1 ) A body of mass 5 kg is moving with a momentum of 10 kg m / s . A force of 0.2 N acts on it in the direction of motion of body for 10 secs . The increase in its kinetic energy is : -

A ) 1.39 J ,                                                 B ) 4.45 J ,

C ) 9.84 J ,                                                 D ) None of these ,

Correct Answer : -   B ) 4.45 J ,

Solution : - 

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2 ) What will be the duration of day and night ( in hour ) , if the diameter of earth is suddenly reduced to half of its original value , the mass remaining constant ?

A ) 2 ,                                                         B ) 6 ,

C ) 14 ,                                                       D ) None of these ,

Correct Answer : -   B ) 6 ,

Solution : -

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3 ) If momentum is increased by 20 % , then kinetic energy increases : -

A ) 11 % ,                                                   B ) 22 % ,

C ) 44 % ,                                                  D ) None of these ,

Correct Answer : -   C ) 44 % ,

Solution : -

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