Which of the following is an example of kinetic energy?

a boy resting on a park bench

a book sitting on a shelf

a rubber band stretched as far as it can go

a swing moving back and forth

Kinetic Energy is the energy by virtue of object's motion. In first two options, no motion has occurred, so there would be no energy, and kinetic energy can also be seen in a swinging both which is in last option in the question.

In short, Your Answer would be Option D) A swing moving back and forth

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