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Types of Simple Machines

There are mainly six simple machines. They are:

1. Lever 2. Pulley 3. Inclined Plane
6. Wedge
4. Screw 5. Wheel and Axle

Lever

A lever is one of the simplest mechanical devices. A lever consists of a beam or stick or
rod. Scissors, nut-cracker, sea saw, etc. are some good examples of lever.
A simple lever has three parts. The point of support is called fulcrum, the object to be
moved is called load and the force applied to the object is called effort.
The closer the fulcrum and the load, the lesser is the effort. That is why a tall narrow door
swings open more quickly than a wide garden gate. Here are the three classes of levers. E
stands for effort, L for load and F for fulcrum.

Class 1 Lever Class 2 Lever Class 3 Lever

1. First Class Lever: When the fulcrum is in between the load and effort, it is a first
class lever. Examples are scissors, claw, hammer, pliers, etc.

Scissors Claw Hammer Pliers

2. Second Class Lever: When the load is in between the fulcrum and the effort, it is called
the second class lever. Examples are wheel barrow, bottle opener, nut cracker, etc.

Wheel barrow Bottle opener Nut cracker

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