Question

Whenever you move your body you are doing work?

True or false

Answer 1

False, not every motion would be work.

Explanation:

If you are standing and move 2 m horizontally, work has not been done. The force you are exerting is vertical, to keep yourself erect.

`"work" = F*s*costheta`
where `theta` is the angle between the force (up) and the displacement (horizontal). In the case of this example, `theta = 90^@`.

`cos90^@ = 0` so no work was done.

This assumed no resistance during your 2 m trip. But if there had been a door that you had to push open, work would have been done. That is because your force against the door was in the same direction as your motion.

I hope this helps,
Steve