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A block of mass M is hanging over a smoo...

A block of mass M is hanging over a smooth and light pulley through a light string. The other end of the strinig is pulled by a constant force F. The kinetic energy of the block increases by 20J n 1s.

A

the tension in the string is Mg

B

The tension is the string is F

C

The work done by the tension on the block is 20 J in the above 1s.

D

the work done by the force of gravity is -20J in the above 1s.

Text Solution

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The correct Answer is:
B
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