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Question
A freely falling object eventually stops on reaching the ground. What happens to its kinetic energy?
Solution
When a freely falling body eventually stops on reaching the ground, its kinetic energy appears in the form of:
- Collisions cause the body and earth to warm up.
- Sound is created when the body crashes with the earth.
- Potential energy of earth and human body structure. The ground might be depressed where the collision occurs and the body might be twisted. Dissipation of energy is the process whereby the kinetic energy of a freely falling body is lost in an unproductive cycle of energy changes.
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