# Simple Machines & Compound Machines

## Levers

A level has a bar that rotates at a fixed point, called a fulcrum. The force that is applied onto the level is the input force. The object that is being lifted by the lever is called the load. A level is used to apply a force to a load. a first class level is where the fulcrum is between the load and the input force; an example of a first class lever would be a regular balance scale. A second class lever is where the load is between the fulcrum and the input force; an example of a second class lever would be a wheelbarrow. A third class lever is where the input for is in between the fulcrum and the load ; an example of a third class lever would be a hammer.

## Pulley (fixed, moveable, block and tackle)

A simple machine with a grooved wheel that holds a rope or cable.An input force is applied to one end of the cable, and the pulley lifts the object, also called the load, at the other end. a fixed pulley is connected to something that does now move such as a ceiling, and this type of pulley is used by pulling one end then the pulley will lift the other end that would be holding the load.

## Wheel and axle

A simple machine that is made up of two round objects that move together. The larger object is the wheel and the smaller object is the axle.

## Inclined plane

A flat, slanted surface, using an inclined plane to move heavy objects into a truck is easier than lifting the object. the input force is smaller than the object's weight.

## Wedge

Two inclined planes that moved, but like an inclined plane there is a smaller input force but over a larger distance. The output force of the wedge is much greater than the input force.

## Screw

A screw is an inclined plane rapped around a cylinder, and like an inclined plane it is a small force over a long distance. The screw applies a large output force over a short distance.

## Compound Machine

Machine made out of two or more simple machines. A block and tackle is an example of a compound machine, it is made out of two pulleys.