Question - A person holds a bundle of hay over his head for 30 minutes and gets tired. Has he done some work or not? Justify your answer.
Answer -
Work is completed whenever the given 2 conditions are satisfied.
(i) A force acts on the body.
(ii) There’s a displacement of the body by the applying of force in or opposite to the direction of force.
When an individual holds a bundle of fodder over his head, then there’s no displacement within the bundle of fodder. Although, force of gravity is functioning on the bundle, the person isn’t applying any force thereon. Hence, within the absence of force, work done by the person on the bundle is zero.