levers and pulleys g3

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Ch. 10 , Lesson 5( Levers and pulleys )

• How can you make work easier?

• Is a tool that makes work easier to do. What machines do? can change the direction of force you need to do work.

Vocabulary:MachineSimple machinesLeverWheel and axlepulleyObjectives:I will be able to know:Levers and pulleys are machines make work easier.

machine

1

3


• some machines change both the direction and amount of force you need to do work.

• • machine can change the

amount of force you need to do work.


2

3

4


• A machine with few or no moving parts.Vocabulary:

MachineSimple machinesLeverWheel and axlepulleyObjectives:I will be able to know:Levers and pulleys are machines make work easier.

Simple machine

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Ch. 10 , Lesson 5( Levers and pulleys ) Is a straight bar that

moves on a fixed point.All levers have 3 important points.

• Load fulcrum force


Lever1

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load the object being lifted or moved.

force the push or pull that moves the lever. fulcrum the point where the lever turns.


A

B

C

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• Are there different kinds of Levers?

• There are 3 types according to arrange of force, fulcrum and load.


1-the fulcrum is between the force and the load .Ex. pliers2-the force is between the fulcrum and the load .Ex. Baseball bat3-the load is between the force and the fulcrumEx. wheelbarrow

wheel and axle• ex: doorknob• wheel=knob• axle=post that

attaches to its center

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Ch. 10 , Lesson 5( Levers and pulleys ) It has a wheel that turns on

a post.The post is called axle


Wheel and axle2

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It makes work easier by change strength of the turning force.The wheel turns a long distance , the axle turns a short distance.


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Other examples for wheel and axle:A windlass a bucket tied to a rope to raise water from a well.


pulley

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Ch. 10 , Lesson 5( Levers and pulleys ) It uses a wheel and a rope

to lift a load.You pull down to lift up.


pulley3

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We have 2 kinds of pulleys One-wheel two-wheelPulley pulley

The force less force is And load needed to Are equal move load


levers and pulleys g3

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