Work Done by a Varying Force
How do we "handle" a force that is not constant? That is, how much work is done by a varying force? We know how to find the work done by a constant force,
W = F s cos How much work is done by a varying force such as this one?
Since we do know how to handle a constant force, we can break this one up into "average values" over small distance x, like this,
Each of these little rectangles has an "area" of (Fx)(x); this is an amount of work W. That is
W = Fx x for each of these little rectangles. The total amount of work done is the sum of these rectangles,
WTot = W = W W = Fx x
In the limit, as we make x smaller and smaller, this sum becomes an integral,
Scalar Product Kinetic Energy Return to ToC, Ch7, Work and Energy (c) Doug Davis, 2001; all rights reserved