1. Chapter Nine: Simple Machines
9.1 Types of Simple Machines

2. 9.1 Using Machines
A machine is a device with moving parts that work together to accomplish a task.
A bicycle is a good example.

3. 9.1 Using Machines
The input includes everything you do to make the machine accomplish a task, like pushing on the bicycle pedals.
The output is what the machine does for you, like going fast or climbing a steep hill.

4. Examples of Simple Machines
A simple machine is an unpowered mechanical device, such as a lever.

5. 9.1 Review of energy
A rope and pulley machine illustrates a rule that is true for all processes that transform energy.
The total energy or work output can never be greater than the total energy or work input.

6. 9.2 Mechanical advantage
Mechanical advantage is the ratio of output force to input force. Machines multiply force.