The word “work” has a variety of meanings in everyday language: effort, labor, employment, or task. In physics, work has a specific meaning; work done by a constant force on an object is defined to be the product of the magnitude of the applied force times the distance through which the force acts. In an equation:
In situations where the force is not parallel to the distance traveled, we use only that part of the force that is parallel. The equation then becomes:
We can see the difference if we think about a boy pulling a little red wagon.
We exert a force across the ground and up.
It is only the force across the ground that counts in the determining the
work.
The unit for work is the Joule or J. Since the unit for force is the newton (N) and the unit for distance is the meter (m) it is not surprising that 1 J is equal to 1 a newton-meter (N·m).
