Lever and its types

1. LEVER
A lever may be defined as a “rigid bar that is used
to overcome a resistance when a force is applied to
one side of the fulcrum .

2. FUNCTION OF A LEVER
•THE FULCRUM
It’s a point at which lever rotates or turns and which identifies
the lever class by it’s position in relation to the other two part

3. •THE FORCE ARM
It’s the point at which the force is applied.

4. •THE LOAD/RESISTANCEARM
It is the point where the load or resistance is located.

5. EXAMPLES OF LEVER

6. • THE FIRST CLASS LEVER - In first class lever, the fulcrum is
between the effort force and the resistance.
EXAMPLES – scissor, seesaw, hammer claw, pliers.
THETYPES OF LEVER

7. • THE SECOND CLASS LEVER - In the second class lever, the
resistance force is between the effort force and the
fulcrum.
EXAMPLES - nutcracker, wheelbarrow, bottle opener.

8. •THETHIRD CLASS LEVER - In the third class lever, the effort
force is between the resistance force and the fulcrum.
• EXAMPLES – broom, fishing rod, ice or sweet holder.

9. Force
•Force is a push or a pull acting on a body .
• A force is characterized by its magnitude,direction,and
point of application to a given body.
•All motion is created by a force.

10. TYPES OF FORCES
EXTERNAL FORCE (non conservative force) - It is any force that causes
change in mechanical energy of a system.
- When a net work is done on an object ,its mechanical energy changes.
INTERNAL FORCE (conservative force) –internal forces are forces
exchanged by objects in the system .
- Mechanical energy does not changes .

12. THANK YOU