1. Six Simple Machines levers screw wedge inclined plane pulley
wheel & axle

2. lever
(Pictures on p. 459)
1st class lever – changes direction and size of the force
Example: shovel, crowbar, see-saw
2nd class lever – use this type of lever if you need greater output force
Example: bottle opener, wheel barrow
3rd class lever – use this lever to increase speed of the end of the lever, or to reduce the distance over which you apply the force
Example: baseball bat, tennis racket, rake, broom
1st Class
2nd Class
3rd Class

3. screw Def: An inclined plane wrapped around a cylinder or a cone
Reduces force and increases distance
Used to raise or lower weights
Can fasten objects because of friction
Ex: spiral notebook
lid on bottle or jar

4. wedge Def: a machine that is thin at one end and thick at the other
Used to cut, split, or pierce objects; to hold objects together
Example: knife blade, doorstop, tip of nail, chisel, scissors, axe blade
single edge double edge

5. Inclined plane Def: a simple machine that is a sloping surface
The less steep an inclined plane is, the less force needed to move an object on the plane.
A less steep plane needs more distance to move an object.

6. Pulley
Def: a pulley is a wheel with a grooved rim and a rope or cable that rides in the groove
Fixed pulley – changes direction
Moveable pulley – multiplies the force
Block & Tackle –
reduces the force
needed to lift
heavy objects

7. Wheel & Axle
Def: a wheel & axle acts like a rotating collection of levers and the axle is the fulcrum
Examples: screwdriver, steering wheels, doorknobs, fans