Question

State the conditions under which the work done by a force are zero intext:zigya

Answer 1

There are two conditions for the work done to be zero.
1) When the work done is extremely slowly done.
2) Work = F. s. cosΦ
Cos Φ is the angle between the force applied and work done. When Φ is 90°, the value of cos 90 is 0. So, the work done also becomes zero.

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Answer 2

if an object is held perpendicular to the ground the angle made will be 90° and according to the formula F.S.COSa and this will result in the work to be zero
consider a person who pick up weights and stood still according to him he has done work but he has not been displaced so his work will be zero