| A | B |
|---|
| force | To push or pull. |
| gravity | the force that makes objects pull towards each other. |
| friction | the force caused by two objects rubbing together that slows down or stops moving objects. |
| work | something done whenever a force makes an object move a distance. |
| energy | the ability to do work. |
| simple machine | one of six kinds of tools with few or no moving parts that make work easier. |
| lever | a simple machine made of a bar that is supported at some point. |
| fulcrum | a point on which a lever is supported and turns. |
| load | an object that is being moved. |
| inclined plane | a simple machine that is a flat surface with one end higher than the other. |
| wedge | a simple machine used to cut or split an object. |
| screw | a simple machine used to hold objects together. |
| wheel and axel | a simple machine with a center rod attached to a wheel. |
| gear | a wheel with jagged edges like teeth. |
| pulley | a simple machine made of a wheel and a rope. |
