3.1 What is Energy?

Examples

Practice Quiz:

1. Energy loss due to friction is:

A. A bad thing.
B. A good thing.
C. Can be good or bad (depending on the situation).

2. Devices used to convert kinetic energy to heat is:

A. Batteries
B. Brakes.
C. Tires.

3. Friction can:

A. Remove kinetic energy from a system (changing to heat).
B. Add kinetic energy to a system.
C. Both.

Disc brakes

Holes in Disc Brakes
There are three main reason that manufacturers add holes to disc brakes 1) reduce weight of the disc  2) allow the disc to cool more during long descents and 3) to allow another place for water to move off the disc.