Simple MachinesSimple MachinesSimple MachinesSimple Machines

Mr. King’s Science ClassesMr. King’s Science Classes

IntroductionIntroductionIntroductionIntroduction

Simple machines are machines with few or Simple machines are machines with few or no moving parts.no moving parts.

There are 7 main Simple Machines.There are 7 main Simple Machines.

Kinds of Simple MachinesKinds of Simple MachinesKinds of Simple MachinesKinds of Simple Machines

We will be learning about the seven simple We will be learning about the seven simple machines. They are:machines. They are: 1. Lever1. Lever 2. Inclined Plane2. Inclined Plane 3. Wedge3. Wedge 4. Screw4. Screw 5. Wheel and Axle5. Wheel and Axle 6. Pulley6. Pulley 7. Gears7. Gears

Energy and WorkEnergy and WorkEnergy and WorkEnergy and Work

Suppose you needed to move an object. Suppose you needed to move an object. You might use tools to help you. Simple You might use tools to help you. Simple machines are tools that use energy to do machines are tools that use energy to do work.work.

Energy is the ability to do work.Energy is the ability to do work. You probably have used several of the You probably have used several of the

seven kinds of simple machines.seven kinds of simple machines.

1. What is a Lever?1. What is a Lever?1. What is a Lever?1. What is a Lever?

A hammer is a lever that helps do work.A hammer is a lever that helps do work. Work is done whenever force makes an Work is done whenever force makes an

object move.object move.

There are 3 different kinds or There are 3 different kinds or “classes” of levers.“classes” of levers.

• First Class LeverFirst Class Lever

• First Class LeverFirst Class Lever

forceforce

• First Class LeverFirst Class Lever

forceforce

fulcrumfulcrum

• First Class LeverFirst Class Lever

forceforce

fulcrumfulcrum

weightweight

• First Class LeverFirst Class Lever

•By moving the fulcrum, the dynamics of the lever By moving the fulcrum, the dynamics of the lever change. Here is how: change. Here is how:

forceforce

fulcrumfulcrum

weightweight

• First Class LeverFirst Class Lever

•By moving the fulcrum, the dynamics of the lever By moving the fulcrum, the dynamics of the lever change. Here is how: change. Here is how:

forceforce

fulcrumfulcrum

weightweight

Requires Requires more force more force to move the to move the weight but weight but less distanceless distance

• First Class LeverFirst Class Lever

•By moving the fulcrum, the dynamics of the lever By moving the fulcrum, the dynamics of the lever change. Here is how: change. Here is how:

forceforce

fulcrumfulcrum

weightweight

Requires Requires more force more force to move the to move the weight but weight but less distanceless distance

• First Class LeverFirst Class Lever

•By moving the fulcrum, the dynamics of the lever By moving the fulcrum, the dynamics of the lever change. Here is how: change. Here is how:

forceforce

fulcrumfulcrum

weightweight

Requires Requires more force more force to move the to move the weight but weight but less distanceless distance

• First Class LeverFirst Class Lever

•By moving the fulcrum, the dynamics of the lever By moving the fulcrum, the dynamics of the lever change. Here is how: change. Here is how:

forceforce

fulcrumfulcrum

weightweight

Requires Requires more force more force to move the to move the weight but weight but less distanceless distance

• First Class LeverFirst Class Lever

•By moving the fulcrum, the dynamics of the lever By moving the fulcrum, the dynamics of the lever change. Here is how: change. Here is how:

forceforce

fulcrumfulcrum

weightweight

Requires Requires more force more force to move the to move the weight but weight but less distanceless distance

• First Class LeverFirst Class Lever

•By moving the fulcrum, the dynamics of the lever By moving the fulcrum, the dynamics of the lever change. Here is how: change. Here is how:

forceforce

fulcrumfulcrum

weightweight

Requires Requires more force more force to move the to move the weight but weight but less distanceless distance

The weight moves The weight moves a greater distance a greater distance than the force.than the force.

• First Class LeverFirst Class Lever

•By moving the fulcrum, the dynamics of the lever By moving the fulcrum, the dynamics of the lever change. Here is how: change. Here is how:

forceforce

fulcrumfulcrum

weightweight

Requires Requires more force more force to move the to move the weight but weight but less distanceless distance

The weight moves The weight moves a greater distance a greater distance than the force.than the force.

• First Class LeverFirst Class Lever

•By moving the fulcrum, the dynamics of the lever By moving the fulcrum, the dynamics of the lever change. Here is how: change. Here is how:

•Now, move the fulcrum clear to the right and Now, move the fulcrum clear to the right and notice the difference.notice the difference.

forceforce

fulcrumfulcrum

weightweight

• First Class LeverFirst Class Lever

•By moving the fulcrum, the dynamics of the lever By moving the fulcrum, the dynamics of the lever change. Here is how: change. Here is how:

•Now, move the fulcrum clear to the right and Now, move the fulcrum clear to the right and notice the difference.notice the difference.

forceforce

fulcrumfulcrum

weightweight

• First Class LeverFirst Class Lever

•By moving the fulcrum, the dynamics of the lever By moving the fulcrum, the dynamics of the lever change. Here is how: change. Here is how:

•Now, move the fulcrum clear to the right and Now, move the fulcrum clear to the right and notice the difference.notice the difference.

forceforce

fulcrumfulcrum

weightweight

• First Class LeverFirst Class Lever

•By moving the fulcrum, the dynamics of the lever By moving the fulcrum, the dynamics of the lever change. Here is how: change. Here is how:

•Now, move the fulcrum clear to the right and Now, move the fulcrum clear to the right and notice the difference.notice the difference.

forceforce

fulcrumfulcrum

weightweight

• First Class LeverFirst Class Lever

•By moving the fulcrum, the dynamics of the lever By moving the fulcrum, the dynamics of the lever change. Here is how: change. Here is how:

•Now, move the fulcrum clear to the right and Now, move the fulcrum clear to the right and notice the difference.notice the difference.

forceforce

fulcrumfulcrum

weightweight

• First Class LeverFirst Class Lever

•By moving the fulcrum, the dynamics of the lever By moving the fulcrum, the dynamics of the lever change. Here is how: change. Here is how:

•Now, move the fulcrum clear to the right and Now, move the fulcrum clear to the right and notice the difference.notice the difference.

forceforce

fulcrumfulcrum

weightweight

Now you have just Now you have just the opposite, less the opposite, less force to move the force to move the weight but more weight but more distance.distance.

• First Class LeverFirst Class Lever

•By moving the fulcrum, the dynamics of the lever By moving the fulcrum, the dynamics of the lever change. Here is how: change. Here is how:

•Now, move the fulcrum clear to the right and Now, move the fulcrum clear to the right and notice the difference.notice the difference.

forceforce

fulcrumfulcrum

weightweight

Now you have just Now you have just the opposite, less the opposite, less force to move the force to move the weight but more weight but more distance.distance.

• First Class LeverFirst Class Lever

•By moving the fulcrum, the dynamics of the lever By moving the fulcrum, the dynamics of the lever change. Here is how: change. Here is how:

•Now, move the fulcrum clear to the right and Now, move the fulcrum clear to the right and notice the difference.notice the difference.

forceforce

fulcrumfulcrum

weightweight

Now you have just Now you have just the opposite, less the opposite, less force to move the force to move the weight but more weight but more distance.distance.

• First Class LeverFirst Class Lever

•By moving the fulcrum, the dynamics of the lever By moving the fulcrum, the dynamics of the lever change. Here is how: change. Here is how:

•Now, move the fulcrum clear to the right and Now, move the fulcrum clear to the right and notice the difference.notice the difference.

forceforce

fulcrumfulcrum

weightweight

Now you have just Now you have just the opposite, less the opposite, less force to move the force to move the weight but more weight but more distance.distance.

• First Class LeverFirst Class Lever

•By moving the fulcrum, the dynamics of the lever By moving the fulcrum, the dynamics of the lever change. Here is how: change. Here is how:

•Now, move the fulcrum clear to the right and Now, move the fulcrum clear to the right and notice the difference.notice the difference.

forceforce

fulcrumfulcrum

weightweight

Now you have just Now you have just the opposite, less the opposite, less force to move the force to move the weight but more weight but more distance.distance.

• First Class LeverFirst Class Lever

•By moving the fulcrum, the dynamics of the lever By moving the fulcrum, the dynamics of the lever change. Here is how: change. Here is how:

•Now, move the fulcrum clear to the right and Now, move the fulcrum clear to the right and notice the difference.notice the difference.

forceforce

fulcrumfulcrum

weightweight

Now you have just Now you have just the opposite, less the opposite, less force to move the force to move the weight but more weight but more distance.distance.

The The weight weight does not does not move move very very much.much.

Can you guess what would be the dynamics if the fulcrum was

directly in the middle?

Can you guess what would be the dynamics if the fulcrum was

directly in the middle?

Can you guess what would be the dynamics if the fulcrum was

directly in the middle?

Can you guess what would be the dynamics if the fulcrum was

directly in the middle?Just a change in directionJust a change in direction

Now for the 2nd class lever.Now for the 2nd class lever.

forceforce

fulcrumfulcrum

weightweight

How would changing the position of How would changing the position of the weight change the dynamics of the weight change the dynamics of this lever?this lever?

Now for the 3rd class lever.Now for the 3rd class lever.

forceforce

fulcrumfulcrum

weightweight

How would changing the position of How would changing the position of the force change the dynamics of this the force change the dynamics of this lever?lever?

2. What is an Inclined Plane?2. What is an Inclined Plane?

A ramp is an inclined plane.A ramp is an inclined plane. A ramp helps move objects.A ramp helps move objects. You can use an inclined plane to help move You can use an inclined plane to help move

an object to a higher or lower place.an object to a higher or lower place.

What is the mechanical advantage of the ramp or incline

plane?

What is the mechanical advantage of the ramp or incline

plane?forceforce

weightweight

What do you notice about the What do you notice about the difference between these two ramps?difference between these two ramps?

What is the mechanical advantage of the ramp or incline

plane?

What is the mechanical advantage of the ramp or incline

plane?forceforce

weightweight

What do you notice about the What do you notice about the difference between these two ramps?difference between these two ramps?

What is the mechanical advantage of the ramp or incline

plane?

What is the mechanical advantage of the ramp or incline

plane?forceforce

weightweight

What do you notice about the What do you notice about the difference between these two ramps?difference between these two ramps?

What is the mechanical advantage of the ramp or incline

plane?

What is the mechanical advantage of the ramp or incline

plane?forceforce

weightweight

What do you notice about the What do you notice about the difference between these two ramps?difference between these two ramps?

What is the mechanical advantage of the ramp or incline

plane?

What is the mechanical advantage of the ramp or incline

plane?forceforce

weightweight

What do you notice about the What do you notice about the difference between these two ramps?difference between these two ramps?

What is the mechanical advantage of the ramp or incline

plane?

What is the mechanical advantage of the ramp or incline

plane?forceforce

weightweight

What do you notice about the What do you notice about the difference between these two ramps?difference between these two ramps?

What is the mechanical advantage of the ramp or incline

plane?

What is the mechanical advantage of the ramp or incline

plane?forceforce

weightweight

What do you notice about the What do you notice about the difference between these two ramps?difference between these two ramps?

What is the mechanical advantage of the ramp or incline

plane?

What is the mechanical advantage of the ramp or incline

plane?forceforce

weightweight

What do you notice about the What do you notice about the difference between these two ramps?difference between these two ramps?

What is the mechanical advantage of the ramp or incline

plane?

What is the mechanical advantage of the ramp or incline

plane?forceforce

weightweight

What do you notice about the What do you notice about the difference between these two ramps?difference between these two ramps?

What is the trade off between these two ramps?What is the trade off between these two ramps?

3. What is a Wedge?3. What is a Wedge?

A doorstop is a wedge.A doorstop is a wedge. A wedge is a simple machine used to push A wedge is a simple machine used to push

objects apart.objects apart. An ax is a wedge that splits wood.An ax is a wedge that splits wood. A wedge could be consideredA wedge could be considered

a two sided incline plane.a two sided incline plane.

4. What is a Screw?4. What is a Screw?

A screw is a simple machine used to hold A screw is a simple machine used to hold objects together.objects together.

Think about your desk.Think about your desk. Does it have screws helping to hold it Does it have screws helping to hold it

together?together? A screw is an inclineA screw is an incline

plane twisted on itself.plane twisted on itself.

5. What is a Wheel and Axle?5. What is a Wheel and Axle?

A wheel and axle is a simple machine made A wheel and axle is a simple machine made of a rod attached to the center of a wheel.of a rod attached to the center of a wheel.

The axle, or rod, turns when you put force The axle, or rod, turns when you put force on the wheel.on the wheel.

You probably have seen a wheel and axle You probably have seen a wheel and axle on scooters, cars, roller skates, and wagons.on scooters, cars, roller skates, and wagons.

6. What is a Pulley?6. What is a Pulley?

A pulley is a simple machine with a wheel A pulley is a simple machine with a wheel and with a rope.and with a rope.

The rope fits around the edge of the wheel.The rope fits around the edge of the wheel. You can use a pulley to move a load up, You can use a pulley to move a load up,

down or sideways.down or sideways.

How do Pulleys Work?How do Pulleys Work?

They can change They can change direction of the load.direction of the load.

forceforce

weightweight

How do Pulleys Work?How do Pulleys Work?

They can change They can change direction of the load.direction of the load.

forceforce

weightweight

OROR

How do Pulleys Work?How do Pulleys Work?

Using two different Using two different pulleys, with the pulleys, with the weight attached to the weight attached to the bottom one with give bottom one with give you a mechanical you a mechanical advantage.advantage.

forceforce

weightweight

How do Pulleys Work?How do Pulleys Work?

Using two different Using two different pulleys, with the pulleys, with the weight attached to the weight attached to the bottom one with give bottom one with give you a mechanical you a mechanical advantage.advantage.

forceforce

weightweight

This is called a block and This is called a block and tackle. You will use less force tackle. You will use less force to lift the weight but will have to lift the weight but will have to pull more rope.to pull more rope.

How do Pulleys Work?How do Pulleys Work?

Using two different Using two different pulleys, with the pulleys, with the weight attached to the weight attached to the bottom one with give bottom one with give you a mechanical you a mechanical advantage.advantage.

forceforce

weightweight

This is called a block and This is called a block and tackle. You will use less force tackle. You will use less force to lift the weight but will have to lift the weight but will have to pull more rope.to pull more rope.

How do Pulleys Work?How do Pulleys Work?

Using two different Using two different pulleys, with the pulleys, with the weight attached to the weight attached to the bottom one with give bottom one with give you a mechanical you a mechanical advantage.advantage.

forceforce

weightweight

This is called a block and This is called a block and tackle. You will use less force tackle. You will use less force to lift the weight but will have to lift the weight but will have to pull more rope.to pull more rope.

How do Pulleys Work?How do Pulleys Work?

Using two different Using two different pulleys, with the pulleys, with the weight attached to the weight attached to the bottom one with give bottom one with give you a mechanical you a mechanical advantage.advantage.

forceforce

weightweight

This is called a block and This is called a block and tackle. You will use less force tackle. You will use less force to lift the weight but will have to lift the weight but will have to pull more rope.to pull more rope.

How do Pulleys Work?How do Pulleys Work?

Using two different Using two different pulleys, with the pulleys, with the weight attached to the weight attached to the bottom one with give bottom one with give you a mechanical you a mechanical advantage.advantage.

forceforce

weightweight

This is called a block and This is called a block and tackle. You will use less force tackle. You will use less force to lift the weight but will have to lift the weight but will have to pull more rope.to pull more rope.

7. What is a Gear?7. What is a Gear?

Two toothed wheels fit together either Two toothed wheels fit together either directly or through a chain or belt.directly or through a chain or belt.

Some gears may have a screw or a toothed Some gears may have a screw or a toothed shaft in place of one of the wheels.shaft in place of one of the wheels.

A gear may also be a combination of A gear may also be a combination of toothed wheels that produces a certain toothed wheels that produces a certain speed like in a bicycle.speed like in a bicycle.

What This MeansWhat This Means

Simple machines are important to us in our Simple machines are important to us in our daily life.daily life.

They help us do work.They help us do work. They make our lives easier.They make our lives easier.