The lever

Lever is a simple form of machine.

There are parts of a lever

1. The effort
2. The load
3. The fulcrum

These three parts can exist in three arrangements.

1. Effort-Fulcrum-Load  EFL
2. Effort-Load-Fulcrum  ELF
3. Fulcrum-Effort-Load  FEL

The Effort-Fulcrum-Load machine ,  EFL.

The Effort-Fulcrum-Load  OR First order  lever  machines, is a machine in which the arrangement of the acting forces are Effort-Fulcrum-Load  . The fulcrum comes in between the Effort and the Load.

The general arrangement is as shown below

Where a and b are the distance move by load and distance move by effort respectively.

From the Principle of moment (The Principle of Moments )

Example of Effort-Fulcrum-Load   machines are;

1. Claw Hammer.

2. Crow bar

3. Pliers

The Effort-Load-Fulcrum  ELF or Second order levers machines

These are the levers machine in which the load is between the Effort and the fulcrum.

From the Principle of moment (The Principle of Moments )

Example of Effort-Load-Fulcrum  machines are;

Nut cracker

Wheel barrow

The Fulcrum- Effort-Load  FEL or third order levers machines

These are the levers machine in which the Effort is between the Load and the fulcrum

From the Principle of moment;

Examples are ;

Tongs

Nail cutter

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