Question

A body is acted upon by a force. State two conditions when the work done is zero.

April 8, 2024

Answer

The two conditions for the work done to be zero are,

(i) When there is no displacement of the body on application of force

i.e. S = 0 and

(ii) When displacement is normal to the direction of force

i.e. θ = 90° as cos 90° = 0

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