Work

In a first course in Physics you typically look at the work that a constant force, F, does when moving an object over a distance of d.  In these cases the work is,

However, most forces are not constant and will depend upon where exactly the force is acting.  So, let’s suppose that the force at any x is given by F(x).  Then the work done by the force in moving an object from x = a to x = b is given by,