Simple Machines

Sikes & West

S4P3a: Identify simple machines and their uses.

S

imple machines make work

easier for us by allowing

us to push or pull over

increased distances.

T

here are 6 types of simple

machines.

What are simple machines?

A

lever is made up of 2 parts:

a bar and a fixed point.

T

he fixed point is called a

fulcrum.

T

here are 3 types of levers.

Lever

Three Types of Levers

M

akes it easier to lift a heavier load.

T

here are fixed pulleys and

moveable pulleys.

T

he picture to the right is a fixed

pulley. A fixed pulley only changes

the direction of force, you pull

down on the string and the load

goes up.

Pulley

A

wedge changes a downward

or forward force into a

sideways force.

A

wedge is an object with at

least one slanting side ending

in a sharp edge, which cuts

material apart.

Wedge

A

n inclined plane is a simple machine with

one flat slanted surface. This holds up

and supports most of the weight load.

A

nother way to describe an inclined plane

is to say that it is a slanting surface

connecting a lower level to a higher level.

T

he most common inclined plane is a

ramp.

I

t does not use much force, but you do

have to move the load farther.

Inclined Plane

A

screw is an inclined plane

twisted into a spiral.

A

screw holds things

together or lifts materials.

Screw

A

wheel and axle has two parts- a wheel

with a axle going through the middle of

the wheel.

Y

ou only need to use a small force on the

wheel.

T

he axle turns the force into a larger

force, which moves the load.

A

doorknob is an example of a wheel and

axle.

Wheel and Axle

U

sing two or more simple

machines.

M

ost machines are compound

machines.

C

an you name some examples of

other compound machines not

shown here?

Compound Machines