Physics
Assertion (A): When a force retards the motion of a body, the work done by the body is zero.
Reason (R): Work done depends on the angle between force and displacement.
- Both A and R are true.
- Both A and R are false.
- A is false but R is true.
- A is true but R is false.
Work, Energy & Power
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Answer
A is false but R is true.
Explanation
Assertion (A) is false. When the force retards the motion, the work done is negative not zero.
Reason (R) is true. Work done depends on the angle between force and displacement W = F x S cos θ and cos 180 is -1, hence, W = - F x S
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