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Question
A pebble is thrown up. It goes to a height and then comes back on the ground. State the different changes in form of energy during its motion.
Solution
The stone continues to rise in height as it is hurled. Kinetic energy falls while potential energy rises. The body has 0 KE and solely P.E. at its peak. Now, as the stone moves closer to the ground, its height decreases and P.E. also decreases. However, as speed increases, KE. increases, and at zero height on the ground, P.E. is zero and K.E. converts to heat, sound, etc.
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