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Question
The potential energy of a freely falling object decreases progressively. Does this violate the law of conservation of energy? Why?
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Solution
- The process does not violate the law of conservation of energy. This is because when the body falls from a height, then its potential energy changes into kinetic energy progressively.
- A decrease in the potential energy is equal to an increase in the kinetic energy of the body. During the process, total mechanical energy of the body remains conserved.
- Therefore, the law of conservation of energy is not violated.
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