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Question
A force of 50 N acts on a body and moves it a distance of 4 m on horizontal surface. Calculate the work done if the direction of force is at an angle of 60° to the horizontal surface.
Solution
We have a situation in which, work is done by force acting obliquely.
Force, (F) = 50 N
Distance travelled by the body, (S) = 4 m
Angle between force and direction of distance, (θ) = 60°
We have a relation as,
W = (F)(S) cos θ
So,
`W = (50) (4) cos 60^circ`
= `200 (1/2)` J
= 100 J
So , the work done is 100 J .
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