Question

A body of mass m falls through a height h. Obtain an expression for the work done by the force of gravity.

April 8, 2024

Answer

When body of mass m falls through a height (h) either vertically or on an inclined plane work is said to be done.

We know, work done is

W = F x S

However, the force of gravity on the body is F = mg acting vertically downwards and the vertical displacement in the direction of force is S = h.

Applying the values of F and S we get,

Work done by the force of gravity is

W = F x S = m x g x h

💡 Some Related Questions

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(b) What is the total mechanical energy at point C?
(c) What is the speed of the bob at position A when released from position B ? (Take g = 10 ms^-2)

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