CHAPTER 14

Energy Conservation

IN THIS CHAPTER
Summary: While kinematics can be used to predict the speeds of objects with constant acceleration, energy conservation is a more powerful
tool that can predict how objects will move even with a changing acceleration.

Key Ideas
Work is related to kinetic energy through the work–energy theorem.
There are many types of potential energy. Two (due to gravity and due to a spring) are discussed in this
chapter.
To use conservation of energy, add potential + kinetic energy at two positions in an object’s motion.
This sum must be the same everywhere.
A potential energy function can be derived for any conservative force.

Relevant Equations

The definition of work:

W = F ·d (^) ||
The work–energy theorem:
W (^) net = ΔK
The force of a spring:
F = −kx
Two different types of potential energy:
Power: