| A | B |
|---|
| work | use of force to move an object |
| friction | rubbing of one object against another |
| rough surface | more friction |
| resists motion | friction |
| wrench | makes amount of force larger |
| pulley | changes direction of force |
| six | number of simple machines |
| compound machine | simple machine connected to another simple machine |
| gasoline engine | use gasoline as fuel |
| cylinders | 8 tubes in gasoline engine |
| pulley | wheel with a rope around it |
| fulcrum | point that a lever turns on |
| slope | flat surface of an inclined plane |
| energy | machines waste |
| pistons | move up and down |
