A boy is standing with a heavy bag. Which of the following is/are true?

He is spending some energy on the bag.

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He is applying a force on the bag.

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Kinetic energy is converted into potential energy.

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Work done by the boy is zero.

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Solution

The correct options are
B He is applying a force on the bag.
D Work done by the boy is zero.
The boy is applying a force on the bag against gravity. But the bag is not moving. So, displacement of the bag is zero. Work is done when an object is displaced by applying a force on it. So, work done by the boy on the bag is zero. This means, the boy is not spending any energy on the bag. Thus, there is no transformation of energy.

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