Question
When do we say that work is done? Write the formula for the work done by a body in moving up against gravity. Give the meaning of each symbol which occurs in it.

Answer

Work is said to be done when the force applied on a body produces motion in it. Work done by a body in moving up is given by:$W = m \times g \times h$ where $W$ is the work done against the gravity. $m$ = mass of the body. $g$ = acceleration due to gravity.

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