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Question
Define the term 'work'. Write the formula for the work done on a body when a force acts on the body in the direction of its displacement. Give the meaning of each symbol which occurs in the formula.
Solution
Work is said to be done when a force causes a displacement. It is a scalar quantity that is mathematically given by the scalar product of the applied force and displacement caused. Joule is the SI unit of work. It is denoted by ‘J’.
We have a relation as,
W = FS cos θ
Where,
(F) - Force
(W) - Work
(S) - Displacement
θ - Angle between F and S
When F and S are parallel, θ = 0.
Then, work done is, W = FS
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