Simple Machines and Levers

What are Simple Machines?

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

Lever

A lever is a rigid body that is used with a pivot to multiply the effects of an applied force when doing work against a load force.

Levers can be classified into First Class, Second Class or Third Class. Here you can understand the difference between the three classes of levers.

Second Class Lever
-Load between fulcrum and effort

Third Class Lever
-Effort between fulcrum and effort

First Class Lever
-Fulcrum between Load and Effort

Mechanical Advantage

Mechanical advantage is a measure of the force amplification achieved by using a machine or tool

The law of the lever is an example of mechanical advantage

Formula For Mechanical Advantage:
Mechanical Advantage: Output Force / Input Force

Principles Of Moment

Taking moment about the Fulcrum, by the Principle of Moments, in equilibrium,

Sum of anticlockwise moments = Sum of clockwise moments

F1 ✕ D1 = F2 ✕ D2

where F is the force and D is the distance between the force and the pivot.

Mechanical Advantage can be expressed in terms of the Output Force / Input Force. Specifically for lever systems, using the Principle of Moments formula above, the Mechanical Advantage can also be expressed in terms of distances.

Examples of First Class Lever:
Scissors, See-Saw

Examples of Second Class Lever:
Bottle-opener, Wheelbarrow

Tongs( used to kiap food)

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Load : the object you're lifting

Fulcrum: point at which the lever pivots.

Effort: The force applied to make the object move

How to identify/remember these different levers?

F,L,E
1,2,3

Fulcrum, Load, Effort
1st Class if Fulcrum in the middle
2nd Class if Load in the middle
3rd Class if Effort in the middle