| A | B |
|---|
| position | the location of an object |
| motion | a change in the position of an object |
| relative position | a change in an object's position compared to another object |
| speed | the rate at which an object changes position |
| force | a push or a pull |
| friction | a contact force that opposes the motion of an object |
| gravity | a non-contact force that pulls objects toward each other |
| magnetism | a non-contact force that pulls objects containing iron |
| work | what happens when a force moves an object over a distance |
| inclined plane | a slanting surface that connects a lower level to a higher level |
| screw | an inclined plane wrapped around a post |
| wedge | two inclined planes used to split, cut, and fasten things |
| lever | a machine with a fulcrum, load, and force used to move and lift things |
| pulley | a machine that changes the direction of motion of an object to which a force is applied |
| wheel and axle | a simple machine made of a wheel and a rod joined to the center of the wheel |
