Simple Machines Helping us lift, lower, fasten, split, cut, divide, and move!

Simple Machines

Helping us lift, lower, fasten, split, cut, divide, and move!

What is a Simple Machine?A simple machine

has few or no moving parts.

Simple machines make work easier

http://www.cosi.org/files/Flash/simpMach/sm1.swf

Simple MachinesThere are 6 simple machines

Wheel and AxlesPulleys Inclined PlanesWedgesScrewsLevers

Wheels and Axles A wheel and axle is a lever

that rotates in a circle around a center point or fulcrum.

The axle is a rod that goes through the wheel which allows the wheel to turn

Makes it easy to move things by lifting or rolling them, and reducing friction


Examples: car, bicycle, office chair, wheel barrow,

shopping cart, door handlehand truck, roller skates

Wheels and AxlesGears are a form of a wheel and axleA gear is a wheel with teeth. The teeth fit in between each other and

turn. When one gear turns, its teeth push

against the teeth of the other gear and they both turn.

There are gears on your bike, on a can opener and on an egg beater.

Pulleys Pulleys 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

Makes lifting heavy weights easier by redirecting force

Pulleys let you move loads up, down, or sideways.


Types of Pulleys A fixed pulley is a pulley in

which the wheel does not move A moveable pulley does not change the direction of

the effort force but does increase the size of the force. When you pull on the rope, the pulley and the load come up.

A compound pulley, also called a block and tackle, is a combination of a fixed and a movable pulley. This type of pulley changes direction, and yields a gain in force at the same time.

Inclined Planes An inclined plane is a flat

surface that is higher on one end

Inclined planes make the work of moving things easier

Makes it easier to move objects upward; a longer path, but easier lifting


Wedges Two inclined planes

joined back to back. Wedges are used to

split things. Pushes material apart, cuts http://www.cosi.org/files/Fla

sh/simpMach/sm1.swf

Screws A screw is an inclined

plane wrapped around a shaft or cylinder.

The inclined plane allows the screw to move itself when rotated.

Turns rotation into lengthwise movement


Screws are inclined planes wrapped around a cylinder. They also act like a wedge albeit with just one edge to separate things. The more gentle the curving, the less force needed but it is needed over a longer distance. If you have tighter curving, you need more force and move less distance as the screw turns.

Levers-First Class In a first class lever the

fulcrum is in the middle and the load and effort is on either side

Helps lift heavy weights using longer distances

Think of a see-saw http://www.cosi.org/files/

Flash/simpMach/sm1.swf

Levers-Second Class In a second class

lever the fulcrum is at the end, with the load in the middle

Think of a wheelbarrow

Levers-Third Class In a third class lever

the fulcrum is again at the end, but the effort is in the middle

Think of a pair of tweezers

SUMMARYWedge Pushes material apart, cuts

Wheeland Axle

Makes it easy to move things by rolling them, and reducing friction

Lever Helps lift heavy weights using longer distances

Inclined Plane

Helps lift heavy weights using longer distances

Screw Turns rotation into lengthwise movement

Pulley Makes lifting heavy weights easier by redirecting force

Pulleys let you move loads up, down, or sideways.

Simple Machines Simple Machines

can be put together in different ways to make complex machinery

INVESTIGATE!

MiKids.com EdHeads.org Dirtmeister’s Simple Machines Simple Machines Complete the chart on the following slide with

your partner. Print out 1 copy.

These websites will help you learn more about Simple Machines.

After viewing these websites, you will be able to identify different types of each Simple Machine.

You will also be able to understand more about each type of Simple Machine.

Simple Machine

Diagram Describe how it worksAn unique example

Simple Machines Helping us lift, lower, fasten, split, cut, divide, and move!

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