Question

I was wondering: If Work is the force applied to a body, causing it to move in the same direction to that of the force, can a body do work on itself?

Answer 1

To make it simpler, I'm assuming all the force is applied in the direction of the displacement,.

One can think in rockets, but in that case the rocket pushes on the gas and the gas pushes on the rocket (it shouldn't be considered a work of the rocket on itself).

Or when a person is walking, but in that case the person exerts a force on the ground, and the ground then exerts a force on the person (i.e, it's ot a work done by the person on themself).

What about the act of eating?

I can't think a situation where an object can do work on itself.

Answer 2

If you use a finger on your right had and push down on lets say the palm of your left hand have you done anhy work?