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Question
What should be the angle between the direction of force and the direction of motion of a body so that the work done is zero?
Solution
The relation between work, force, distance and angle between the two is:
W = (F) (S) cos θ
Where,
(W) - Work done
(F) - Force
(S) - Displacement
(θ) - Angle between force and displacement
When the force is perpendicular to the direction of motion, and hence, the work done is also zero.
Example - The work done by the earth on a satellite moving in a circular orbit around it is zero.
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