Question

The force applied against an object moving horizontally on a linear path is described by `F(x)=8-x`. By how much does the object's kinetic energy change as the object moves from `x in [ 0, 4]`?

Answer 1

The kinetic energy of the object will decrease by 24J.

Explanation:

Change in `E_k`
= Work done on object
= Area under the F-x graph

#int_0^4 F(x) dx = int_0^4 (8-x) dx = [8x-0.5x^2]_0^4 = 32-8 = 24#