Question
A body of mass m is taken from the surface of the earth to a height h. What is the change in the potential energy of mass m? Is it equal to mgh?
Solution
At a distance r from the centre of the Earth, gravitational potential energy at a point is given by,
At the surface of the earth,
Gravitational potential energy at height h from the surface of the earth is,
Change in potential energy is,
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Change in potential energy is not equal to mgh.
But if h<<R, then R + h = h
∴ Change in potential energy,
At the surface of the earth,
Gravitational potential energy at height h from the surface of the earth is,
Change in potential energy is,
Change in potential energy is not equal to mgh.
But if h<<R, then R + h = h
∴ Change in potential energy,
