A wheel and axle is a simple machine made up of two circular objects of different size. All wheels need an axle. The wheel and axle must move together to be a simple machine.

The wheel and axle is a simple machine made of a large wheel secured to a smaller wheel which is called an axle.

There are two main ways to use a wheel and axle. The first way is by wrapping a rope around a supported wheel with a lever sticking out. An object can be tied to the other end. By turning the lever, the rope either moves the object toward or away from you. The second way is by having two wheels at the end of a axle. The wheels will then roll providing movement.

Effort applied to the wheel turns the axle, or effort applied to the axle turns the wheel. They move together. When effort is applied to the wheel, the wheel and axle spreads the force over a greater distance. The center rod, or axle, is attached to the wheel. The wheel is one of the most important inventions in history. It spins around to help you get from place to place.

- cars

- roller skates

- bicycles

- wagons

- doorknobs

- ferris wheels

- gears

Here are our sources:

http://www.fi.edu/pieces/knox/automaton/wheel.htm

http://personal.rockbridge.net/higs/sm/wheelax.htm

http://www.usoe.k12.ut.us/curr/science/sciber00/8th/machines/sciber/machine7.htm

http://teacher.scholastic.com/dirtrep/simple/wheel.htm