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