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
Work is done when
- Force is applied
- Displacement takes place
- The angle between the force and displacement is not 90 ° .
When a person holds a bundle of hay over his head,
he applies force to hold it
but there is no displacement.
Since the displacement is zero, no work is done.