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Question
Write an expression for the potential energy of a body of mass m placed at a height h above the earth's surface. State the assumptions made, if any.
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Solution
Expression for potential energy = mgh
Assumptions made :
- Potential energy on the ground is zero.
- The earth's gravitational potential energy increases and its force of attraction diminishes with increasing distance from the body's surface (i.e., the negative value of energy decreases).
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