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A body of mass m starts from rest and moves through a fixed distance under a constant force. The kinetic energy gained by it is directly proportional to

1. m/√m
2. √m
3. 1/√m
4. independent of m

Correct answer: independent of m

Solution

The kinetic energy gained by the body is determined by the work done on it, which is the product of the force and the distance moved. Since the force is constant and the distance is fixed, the kinetic energy is independent of the mass of the body.

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