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Work, Energy and Power

Introduction

Imagine a vendor carrying a basket of vegetables on her head. Is she doing any work? One would definitely say yes! However, in Physics she is not doing any work! Again, imagine a boy pushing against a wall? Is he doing any work? We can see that his muscles are contracting and expanding. He may even be sweating. But in Physics, he is not doing any work!

Definition: Work

When a force exerted on an object causes it to move, work is done on the object (except if the force and displacement are at right angles to each other).

Work, Energy and Power