Work

Work is a force and a displacement in the direction of the force:

Because we are using a displacement instead of distance, what matters is the end result, not the process used to get there.

We are the ones who decide the direction for work: we ask What is the work in __ direction?

The unit for work is the newton-meter() or the Joule . When dealing with subatomic particles we use the electron-volt where .

For work to happen, there must be a in the direction or in the direction. When the force is opposite the direction, there is negative work.

This means we can represent work as a Dot Product:

or:

In terms of components:

We can also say that:

For Rotational Motion, for a rotation from to , work is:

Work Done on a System By External Forces Frictional Work