Q2 of 11 Page 83

A boy is trying to push the concrete pillar of the building using a force of 300 N. Calculate the amount of work done by the boy.

In terms of physics, work is done only when the applied force produces any motion in the object(on which force is applied).

That is, if there is no displacement or no motion of the object on which force is applied then the work done is zero.


In the question, it is given that the force is applied on a concrete pillar, now it is obvious from the question that the pillar will not move from its place. Hence, the force of 300N applied on the pillar does not produce any motion/displacement. So if the displacement is zero,


Amount of work done = force applied × displacement of the object


Work = 300 × 0


Amount of the Work done = 0


Note:-It is necessary to use logic for these type of question for that you have to first understand the question thoroughly.


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