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Work, Energy, Power and Collision — JEE physics STD 12 Science — Question

CBSE BoardEnglish MediumSTD 12 ScienceJEE physicsWork, Energy, Power and Collision1 Mark
Question
Assertion : When the force retards the motion of a body, the work done is zero.
Reason : Work done depends on angle between force and displacement.
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Answer

(e) When the force retards the motion, the work done is negative. Work done depends on the angle between force and displacement $W=F s \cos \theta$

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