have you ever : tried to take a super heavy object up a flight of stairs ? what happened

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Have you ever : Tried to take a super heavy object up a flight of stairs ? WHAT HAPPENED

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Have you ever :

Tried to take a super heavy object up a flight of stairs ? WHAT HAPPENED

Have you ever

Tried to cut a cake with out a knife?

Have you ever

tried to unscrew a nut, bolt, or screw from something with your bare hands and discovered that it was just too tight to loosen even if you had a good grip?

Have you ever

Tried raise the blinds in your house without the strings?

Simple Machines

Machines are tools that make tasks easier.

All machines are built using one or more simple machines.

Simple machines are tools used to make work easier.

You have probably used some simple machines, but did not realize that they were actually

called simple machines!

Simple machines do not make less work; they just make it easier

to do work.

It would be hard to cut this wood without the saw!

The 6 Simple Machines

Lever

Pulley Wheel and Axle

WedgeScrewInclined Plane

There are 6 different types of simple machines:

•(1)lever

•(2)screw

•(3)pulley

• (4)wheel & axle

• (5)inclined plane

• (6)wedge

(1) LEVER

A lever is a stiff bar that moves about a fixed point (fulcrum).

A lever is used to push, pull, or lift things.

A shovel is an example of a lever.

A seesaw is another example of a lever.

(2) SCREW

A screw is an inclined plane wrapped around a cylinder or cone.

A common use of the screw is to hold objects together.

A jar lid and a wood screw are examples of a screw.

So far we have learned about 2 types of simple machines: levers & screws….

(3) PULLEY

A pulley is a wheel that has a rope wrapped around it.

Pulleys can be used to lift heavy objects by changing the direction

or amount of the force.

A flagpole uses a pulley to raise the flag.

Now we have learned about 3 types of simple machines: levers, screws, and pulleys…..

(4) WHEEL & AXLE

A wheel & axle consists of a rod attached to a wheel.

A wheel & axle makes it easier to move or turn things.

A bicycle wheel, roller skates, and a doorknob are all examples of a wheel

& axle.

We now know about 4 types of simple machines: levers, screws, pulleys, and wheels & axles.

(5) INCLINED PLANE

An inclined plane is a flat surface that is raised so that one end is

higher than the other.

An inclined plane helps move heavy objects up or down.

A ramp is an example of an inclined plane.

Let’s add inclined plane to our list of simple machines (along with levers, screws, pulleys, and wheels & axles).

(6) WEDGE

A wedge is wide at one end and pointed at the other to help cut or

split other objects.

Examples of wedges: a knife or an ax

Now you know about the 6 types of simple machines:

(1) LEVER

(2) SCREW

(6) WEDGE

(3) PULLEY

(4) WHEEL & AXLE

(5) INCLINED

PLANE

These simple machines make work easier!

Can you think of other examples of pulleys?

• Did you say either of these:

A pulley that raises and lowers blinds.

The pulley that raises and lowers the flag on a flagpole.

A lever is a type of simple machine.

• A lever uses force to move something.

Here are some examples of levers.

bottle opener seesaw

toilet flusher

Can you think of other examples of levers?

• Did you say either or these?

crowbarscissors

A wheel and axle is a type of simple machine.

• The axle is the rod that holds the wheels together.

Here are some examples of wheel and axles.

rolling pin pencil sharpener

ferris wheel

Can you think of other examples of wheel and axels?

Did you say any of these?

bicycle

skates

wagon

The inclined plane is a simple machine.

• An inclined plane is a slanted surface that can be used to raise or lower things.

• An inclined plane does not move.

These are some examples of inclined planes.

wheelchair ramp boatramp hatchet

Can you think of other examples of inclined planes?

• Did you say any of these?

dump truck ladder rollercoaster

A wedge is a type of simple machine.

• A wedge is two inclined planes that are back to back.

• The difference between an inclined plane is that it does its work by staying still, while a wedge moves.

• Wedges hold things together or split things apart.

These are some examples of wedges.

A fork and a knifescrewdriver

golf club

Can you think of other examples of wedges?

• Did you say any of these?

nail

teeth

ship

A screw is a type of simple machine.

• A screw is an inclined plane that is wrapped around a cylinder with a flat head on one end.

• This head is used to turn or drive the screw into something.

These are some examples of wedges.

swivel stool

bottle lids

corkscrew

Can you think of other examples of screws?

• Did you say any of these?

door lock

light bulb

clamp

As you can see, our world is made up of many simple machines. You can find examples any place you

look.

• Simple machines solve the problem of how to do work faster and easier.

• Maybe you can invent a machine that will make some job faster and easier.

Pulleys

• Pulley are wheels and axles with a groove around the outside

• A pulley needs a rope, chain or belt around the groove to make it do work

Diagrams of Pulleys

Fixed pulley: A fixed pulley changes the direction of a force; however, it does not create a mechanical advantage.

Movable Pulley: The mechanical advantage of a moveable pulley is equal to the number of ropes that support the moveable pulley.

COMBINED PULLEY

• The effort needed to lift the load is less than half the weight of the load.

• The main disadvantage is it travels a very long distance.

A screw is an inclined plane wrapped around a post. Click on the light bulb to learn more.

Axle

Wheel

Click on the windmill to learn more.