Physics
Give an example when work done by the force of gravity acting on a body is zero even though the body gets displaced from its initial position.
Work, Energy & Power
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Answer
When a coolie carrying a load moves on a horizontal platform, the force of gravity acting on him is normal to the displacement of the load i.e. the angle between force and displacement of load is 90°.
Work done by Coolie = F × S Cos 90° = F x S x 0 = 0.
Therefore, in this case work done by the force of gravity is zero even though the load gets displaced from its initial position.
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