# Simple Machines

Lever

Wheel and Axle

Pulley

Screw

Inclined plane

Wedge

## Lever

The earliest remaining writings regarding levers date from the 3rd century BC and were provided by . Give me a place to stand, and I shall move the Earth with it is a remark of Archimedes who formally stated the correct mathematical principle of levers. It is assumed that in ancient Egypt, constructors used the lever to move and uplift obelisks weighing more than 100 tons.

## Wheel and Axle

Wheel and Axle, a simple machine consisting of a wheel or crank and an axle that turn on the same axis. Steering wheels, doorknobs, and screwdrivers are wheel-and-axle devices. A crank replaces the wheel in devices such as windlasses, bicycle pedals, and hand drills.

## Pulley

A pulley is a wheel with a groove along its edge, for holding a rope or cable. Pulleys are usually used in sets designed to reduce the amount of force needed to lift a load. However, the same amount of work is necessary for the load to reach the same height as it would without the pulleys. The magnitude of the force is reduced, but it must act through a longer distance. Pulleys are usually considered one of the simple machines.

## Screw

A screw is a specialized application of the wedge or inclined plane It contains a wedge, wound around an interior cylinder or shaft that either fits into a corresponding plane in a nut, or forms a corresponding plane in the wood or metal as it is inserted. The technical analysis see also statics dynamics to determine the pitch thread shape or cross section, coefficient of friction static and dynamic and holding power of the screw is very similar to that performed to predict wedge behavior.

## Inclined plane

An Inclined plane or a ramp is one of the basic machines. It reduces the force necessary to move a load a certain distanc'e up by providing a path for the load to move at a low angle to the ground. This lessens the needed force but increases the distance involved so that the amount of work stays the same.

## Wedge

A wedge is a simple machine used to separate two objects or portions of objects through the application of force. A wedge is made up of two inclined planes. These planes meet and form a sharp edge. This edge can split things apart.