| A | B |
|---|
| locks, zippers, knife, an axe | examples of inclined planes |
| a wedge and screw | two types of inclined planes |
| six types of simple machines | screw, wedge, lever, pulley, inclined plane, wheel and axle |
| 3 classes of levers | 1st class, 2nd class, 3rd class |
| machine | instrument that makes work easier |
| examples of 1st class levers | crowbar, seesaw, pliers |
| examples of 2nd class levers | wheelbarrows, doors, nutcrackers, bottle openers |
| examples of 3rd clas levers | shovels, baseball bats, hammers, tweezers, fishing poles |
| examples of wheel and axle | screwdriver, bicycles, gears, door knobs |
| power equals | work divided by time |
| power is expressed | watts or joules per second |
| large quantities of power is expressed in | kilowatts |
| input work is | the work that goes into the machine |
| output work is | work done by the machine |
| machines make work easier by | multiplying either the effort or distance |
| the two types of woork involved in using a machine are | input work and output work |
