1. Simple Machines
4th Grade Science
S4P3a

2. S4P3a Students will identify simple machines and explain their uses
Lever
Pulley
Wedge
Inclined plane
Screw
Wheel & Axle

3. What is a simple machine?
A simple machine is a tool that makes work easier.
You use less force when you use some simple machines to get work done.
Others change the direction of your force.

4. Lever A lever is a bar that moves on a fulcrum.
The fulcrum is the center point of a lever.
You use a lever to lift or open things.
Examples include a crowbar, broom, hammer, shovel, or bottle opener.

5. Inclined Plane
An inclined plane is a simple machine with a sloped side.
You use an inclined plane to move things to a higher place.
Examples include a wheelchair ramp, sloped road, or playground slide

6. Wedge A wedge is an inclined plane with two sloped sides.
A wedge is used to split an object or give an outward push to a material.
Examples include a knife, axe, fork, nail, or doorstop.

7. Screw
A screw is an inclined plane that is wrapped around a center rod.
You can use a screw to hold things together or move things.
Examples include a swivel chair, base of a jar lid, lightbulb, or wood screw

8. Wheel & Axle
A wheel and axle is a wheel with a rod attached to the center of it.
You can use it for turning things.
Examples include a doorknob, eggbeater, bicycle wheel, or steering wheel.

9. Pulley A pulley is a wheel with a rope around it.
You use a pulley for lifting or pulling things.
Examples include a flagpole pulley, elevator pulley, window blinds, or a crane.

10. Quiz
1. The wheelbarrow makes work easier because the handles are part of a simple machine called _______________.

11. Quiz
2. A pulley is a simple machine that makes work easier by _____________.

12. Quiz
3. An axe can be used to split wood. The blade of the axe is a simple machine called ______________.