If you're seeing this message, it means we're having trouble loading external resources for Khan Academy.

If you're behind a web filter, please make sure that the domain *.kastatic.org is unblocked.

There are six simple machines. They are as follows: lever, wheel, pulley, incline plane, wedge and screw. This tutorial will cover the first three.

Simple machines can give you a mechanical advantage—in other words they allow you to spread the force you apply to move an object over a distance. This means you don’t have to apply as much force at any given point in time.  Simple machines can make it possible for you to lift something or move something that would be too heavy otherwise.

We recommend you use this tutorial in the following order:

1.     Watch what is happening between each part in the silent exploration videos.

2.     Take notes on what is happening.

3.     Define the parts of each simple machine and look at what is happening between them 

4.     Answer the questions about each silent video.

5.     Work the math problems (for algebra 1 and trig studnets and above) 

6.     Build and test your own LEGO simple machine and see how friction, machine flex, string stretch, air resistance and other factors influence your simple machine.