# The Six Simple Machines

## Lever

-Rigid bar that rotates around a fixed point.

-The fixed point is called the fulcrum.

- Use effort to make the load move.

Class 1: Fulcrum is between the load and the effort.

Class 2: Fulcrum at one end, effort at one end and the load is in the middle.

Class 3: Fulcrum at one end, load at one end, effort in the middle.

Example: Seesaw

## Wheel & Axle

- Small cylinder (axle) joined to a large cylinder (wheel).

- Used to move heavy loads usually across ground.

Example: Car

## Inclined Plane

- Simply a tilted surface

- The steeper the slope the more effort it takes to push/pull something up.

Example: hill

## Wedge

- Two inclined planes sandwiched together

- Changes the force from moving downwards to moving outwards.

Example: hammering a nail into wood

## Screw

- Inclined planes that is coiled around a shaft.

- Converts rotational motion into linear motion.

Example: Spiral stairs

## Pulley

- Makes work easier by changing the direction of the force.

- By allowing the person to pull down on the rope he can add its own weight to the effort rather than just lifting the load.

Example: Elevator