o
o
The work done by the conservative force depends only on the end points.
A third definition states that the work done by this force in a closed path is zero.
o The total mechanical energy of a system is conserved if the forces, doing work on it, are conservative.
Potential energy of spring o
o
The spring force is an example of a variable force, which is conservative.
In an ideal spring, Fs = − kx, this force law for the spring is called Hooke’ s law.
o The constant k is called the spring constant. Its unit is N m-1.