1. Types of levers
Mr. Ahmed Mohammed Hany

2. levers
Some people believe that in the past, levers were the first machines man invented.
Levers were first described in the year 260 B.C by the Greek scientist (Archimedes).

3. What is levers?
Look at this pictures then answer

4. What is levers?
All of the previous machines are similar in shape and size. ( )
All of the previous machines consist of a rigid bar. ( )
These machines are made of the same material. ( )

5. What is levers?
All of the previous machines are used to move an object. ( )
A person inflicts force on each machine. ( )
There is a fixed point that each machine rotates on. ( )

6. We can conclude from the previous that all of the previous machines share in the following:
They consist of a rigid bar (straight or curved).
An effort is exerted to overcome the resistance.
There is a force inflicted by a person to equilibrate the resistance.
There is a fixed point that the bar rotates on called “fulcrum”.

7. levers
It is a rigid bar that rotates around a fixed point called the fulcrum, and is affected by force and resistance

8. the importance of levers:
Increasing force: crowbar and nutcracker.
Increasing distance: manual broom
Increasing speed: hockey bat
Moving the force from one place to another: manual broom
Accuracy in performance: tweezers
Avoid dangers: coal holder

9. types of levers:

10. types of levers:

11. types of levers: