A MACHINE is a tool that helps us do work.

Machines help us by

- - changing the amount of force on an object
  - changing the direction of the force

WORK is the result of force moving an object.

SIMPLE MACHINES have few or no moving parts.

There are 6 types of simple machines.

1. lever
2. incline plane
3. wedge
4. screw
5. wheel and axle
6. pulley

Watch this video to see examples of real simple machines at work.

Real World Science: Simple Machines

A LEVER is made of a board or bar set on top of a fulcrum. It is used to lift weight.

Examples: seesaw, crow bar, baseball bat, rake

kids on a seesaw baseball bat and ball rake

An INCLINED PLANE is a slanted surface to make lifting easier.

Examples: ramp, stairs

ramp

A WEDGE is two inclined planes together used to raise an object or split an object.

Examples: knife, door stop, ax

knife

A SCREW is an inclined plane wrapped around a pole or shaft that is used to hold materials together or drill holes.

Examples: drill bit, screws

screws drill

A WHEEL AND AXLE is a wheel that turns on a post to help move things quickly and easily.

Examples: steering wheel, door knob, screwdriver

steering wheel door knob

A PULLEY is made of rope and string wound around a reel to change the direction of a force.

Examples: flagpole, crane, clothesline, fishing pole

flag pole fishing pole

Simple Machines Song

Source:

“Real World Science: Simple Machines.” Discovery Education, Mazzarella Educational Media, 2014, app.discoveryeducation.com/learn/videos/e3835fc3-2685-4e95-8aaa-6f19831d011b.