Simple Machines

What do machines do? Why do we need machines?

Common Simple Machines…

• First, rank the following words from 0-5 (0= you have never heard of this word & 5= you know the word VERY well). Second, explain what the following terms mean in your own words:a. Machine g. Pulley

b. Simple machines h. Wheel & Axle

c. Work i. Inclined Plane

d. Force j. Wedge

e. Work input/Work output k. Screw

f. Lever l. Compound Machine

YOURS: TEXTBOOK:

• A machine is a device that makes work easier by changing the size or direction of a force.

• Examples: wheelchair, scissors, chopsticks

YOURS: TEXTBOOK:

• Work is the transfer of energy to an object by using a force that causes the object to move in the direction of the force.

• Work is done on an object if two things happen: 1) the object moves as a force is applied, 2) the direction of the object’s motion is the same as the direction of the force.

• Examples: pushing a ball up a hill

OR ORYES NO YES NO

YOURS: TEXTBOOK:• A push or a pull

exerted on an object in order to change the motion of the object; force has size and direction.

• Examples: people, bulldozer, static electricity

YOURS: TEXTBOOK:

• Work input is the work done on the machine.

• Work out put is the work done by the machine.

• Examples: opening a paint can

YOURS: TEXTBOOK:

• A machine or simple device without moving parts.

• Examples: lever, pulley, wheel & axle, inclined plane, wedge, screw

YOURS: TEXTBOOK:

• A machine made up of more than one simple machine.

• Examples: manual can opener

The Six Simple Machines

The Six Simple MachinesLever

The Six Simple MachinesLever Pulley

The Six Simple MachinesLever Pulley Wheel & Axle

The Six Simple MachinesLever Pulley Wheel & Axle

Inclined Plane

The Six Simple MachinesLever Pulley Wheel & Axle

Inclined Plane Wedge

The Six Simple MachinesLever Pulley Wheel & Axle

Inclined Plane Wedge Screw

YOURS: TEXTBOOK:• A lever is a simple

machine that has a bar that pivots at a fixed point, called a fulcrum.

• Examples: first-class lever (see saw), second-class lever (wheelbarrow or soda bottle opener), third-class lever (lifting weights or hammering a nail)

The Six Simple MachinesLever

First-Class Lever Second-Class Lever Third-Class Lever

Elementary School Middle School High School

YOURS: TEXTBOOK:

• A simple machine that has a grooved wheel that holds a rope or a cable.

• Examples: fixed, moveable, block and tackle

The Six Simple MachinesLever Pulley

Types of Pulleys:

YOURS: TEXTBOOK:

• A simple machine consisting of two circular objects of different sizes.

• Examples: car’s wheel & axle, faucet

The Six Simple MachinesLever Pulley Wheel & Axle

The Six Simple MachinesLever Pulley Wheel & Axel

Inclined Plane

YOURS: TEXTBOOK:

• A simple machine that is made up of two inclined planes that move; often used for cutting.

• Examples: knife, axe, door stop

The Six Simple MachinesLever Pulley Wheel & Axel

Inclined Plane Wedge

YOURS: TEXTBOOK:

• A simple machine that consists of an inclined plane wrapped around a cylinder.

• Examples: screw, light bulb

The Six Simple MachinesLever Pulley Wheel & Axel

Inclined Plane Wedge Screw

The Six Simple Machines

Activities• Museum of Science & Industry

• Lemelson Center’s Invention at Play

1. What would be easier, a steep inclined plane or a shallow inclined

plane?

2. What would be easier, a wide wedge or a skinny wedge?

3. What would be easier, a long, skinny screw or a short, fat screw?

4. What would be easier, the fulcrum in the middle or the fulcrum

to one side of the lever?

5. What would be easier, a short axle or a long axle?

6. What would be easier, a wide rope or a skinny rope?