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What is meant by the gravitational potential energy? Derive expression for it. |
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Answer» Gravitational potential energy is the potential energy possessed by a body due to its position relative to the centre of earth. For a body placed at a height above the ground, the gravitational potential energy is measured by the amount of work done in lifting it up to that height against the force of gravity. Let a body of mass m be lifted from the ground to a vertical height h. The least upward force F required to lift the body (without acceleration) must be equal to the force of gravity (=mg) on the body acting vertically downwards. The work done W on the body in lifting it to a height h is W = force of gravity (mg) × displacement (h) =mgh This work is stored in the body when it is at a height h in the form of its gravitational potential energy. Gravitational potential energy U = mgh |
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