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Question
The work done by a force acting obliquely is given by the formula : W = F cos θ ✕ s. What will happen to the work done if angle θ between the direction of force and motion of the body is increased gradually? Will it increase, decrease or remain constant.
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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
Let us see the graph of to understand the dependence of work on the angle between force and distance.
From the graph, we can observe that on increasing the value of angle between force and distance, value of cos θ continuously decreases and becomes negative after `pi/2`.
Hence, if we increase the angle between force and distance gradually, the value of work done will continuously decrease.
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