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.
Explanation GIVEN: A person holding a bundle of hay over his head. TO FIND: Work done by him or not. The person holding a bundle of hay gets tired only due to conversion of chemical energy into thermal energy because of muscular efforts. When someone holds a bundle of hay over his head, then there’s no displacement within the bundle of hay. Although, the force of gravity is working on the bundle and the person is applying a force to resist the weight of the load or this force of gravity. Hence, within the absence of the displacement, work done by the person on the bundle is zero So, no work is done by the person in holding the bundle of hay.
