This document provides an overview of simple machines, including the lever, inclined plane, wedge, screw, wheel and axle, and pulley. It explains that machines help do work by changing the amount or direction of force applied to an object. Energy is required to do work, which is the result of a force moving an object. Gravity is also discussed as the constant force pulling objects toward Earth. Compound machines combine two or more simple machines to work together.

1. Simple Machines
SOL 3.2

2. Machine – a tool that helps us do
work
Machines help us by:
3. Changing the amount of force on an
object.
5. Changing the direction of the force.

3. Force is a push or pull that
changes the motion or shape
of an object.
Example: I push a bookshelf to
move it.

4. Energy is the ability to do
work.
Example: I must have energy to
run the mile.

5. Work is the result of force
moving an object.
Example – Picking up something
heavy is hard work!

6. Gravity
Gravity is the force that constantly
pulls objects toward Earth.

7. Simple machines – have few or
no moving parts
• Lever
• Inclined Plane
• Wedge
• Screw
• Wheel and Axel
• Pulley

8. Lever –made of a board or bar
set on top of a fulcrum. It is used
to lift weight
Example: seesaw, crowbar,
baseball bat, rake

9. Inclined Plan – a slanted
surface to make lifting easier
Example: ramp, stairs

10. Wedge – two inclined planes
together used to raise an object
or split an object.
Example: knife, door wedge, ax

11. Screw – an inclined plane
wrapped around a pole or shaft
that is used to hold materials
together or drill holes.
Example: drill bit, screws

12. Wheel and Axel – a wheel that
turns on a post to help move
things quickly and easily
Example: steering wheel,
doorknob, screwdriver

13. Pulley – made of rope and string
wound around a reel to change
the direction of a force.
Example : flagpole, clothesline,
cranes, fishing reel

14. Compound Machine – two or more
simple machines working together.
Examples:
Bike
Car

15. How Work is Done
Energy Force Function
Work is done!