# Lever: Definition, Principle, and Types

## What is a Lever?

A lever is a simple machine consisting of a beam or rigid rod pivoted at a fixed hinge, or fulcrum. A lever is a rigid body capable of rotating on a point on itself. On the basis of the locations of fulcrum, load and effort, the lever is divided into three types.

It is also a gained mechanical advantage in a mechanical system. It is one of the six simple machines identified by Renaissance scientists. A lever amplifies an input force to provide a greater output force intended to provide leverage.

The ratio of the output force to the input force is the mechanical advantage of the lever. As such, the lever is a mechanical benefit device that balances force against the movement.

A man could lift his weight several times by pulling down on the long arm. It is said that this device was used in Egypt and India as early as 1500 BCE to raise water and raise troops during the war.

There are three parts to all levers:

• Fulcrum – the point at which the lever rotates.
• Input force (also called the effort) – the force applied to the lever.
• Output force (also called the load) – the force applied by the lever to move the load.

### Principal of Lever

It has been found by experiment that two equal forces acting in opposite directions, i.e., clockwise and counterclockwise, and applied to a uniform lever at equal distances from the fulcrum counteract each other and establish a state of equilibrium, or balance, in the lever.

The experiment has also shown that two unequal forces acting in opposite directions. That will bring the magnitude of a force when the magnitude of one force. And its effort arm or lever arm is equal to the product of the magnitude of the other force and the effort arm.

In physics, the product of a force is called the moment of force by its effort; The general conclusion, known as the theory of moments, states that equilibrium is established when the sum of the moments of the forces acting in a counterclockwise direction is equal to the sum of the moments of the forces acting in a counterclockwise direction.

It is possible, as a result, to overcome a very large force at a large distance with a very small force at a large distance from the fulcrum. Archimedes is believed to have a lever in his brain, which gave him a standing place to move the world.

Still confused about the use of a lever and how it works? let’s break down into the pieces for a better understanding.

## Types of Lever

There are three types of levers: first-class, second class, and third class. The difference between the three classes depends on where the force is, where the fulcrum is and where the load is.

### First-Class Lever

First-class levers have the fulcrum between the force and the load. In summary, in a first-class lever, the effort (force) moves over a large distance to move the load a smaller distance, and the fulcrum is between the effort (force) and the load.

Fulcrum between effort and resistance: Effort is applied on one side of the fulcrum and load on the other side. For example, a lead, a crowbar, or a pair of scissors. The mechanical gain may be less than or greater than 1.

#### First-Class lever example

Other examples of first-class levers are pliers, scissors, a crowbar, a claw hammer, a see-saw, and a weighing balance. In summary, in a first-class lever, the effort (force) moves over a large distance to move the load a smaller distance, and the fulcrum is between the effort (force) and the load.

• Our hand pushing an object or seesaws, crowbars.
• Using scissors represents the use of two first-class levers.
• A wheel and axle are also an example.
• Pulling a nail out of a wooden plank also represents a first-class lever.

### Second Class Lever

In second class levers, the load is between the effort (force) and the fulcrum. A common example is a wheelbarrow where the effort moves a large distance to lift a heavy load, with the axle and wheel as the fulcrum. In a second class lever, the effort moves over a large distance to raise the load a small distance.

Note that the length of the effort arm goes all the way to the fulcrum and always exceeds the length of the load arm in the second-class lever.

#### Second class lever examples

In second class levers, the load is between the effort (force) and the fulcrum. A common example is a wheelbarrow where the effort moves a large distance to lift a heavy load, with the axle and wheel as the fulcrum. In a second class lever, the effort moves over a large distance to raise the load a small distance.

• Wheelbarrow
• Crowbar
• Nutcracker
• Bottle opener
• Brake pedal of a car
• Nail clippers

### Third Class Lever

In the third-class levers, the effort is between the load and the fulcrum, for example in barbecue tongs. Other examples of third-class levers are a broom, a fishing rod, and a woomera.

Note that the length of the load arm goes all the way to the fulcrum and always exceeds the length of the effort arm in the third-class levers. In addition, third-class levers are loaded in the same direction as the effort.

Due to the location of the effort in relation to the fulcrum, a bearing or other tool is often required to place the beam as it pivots. Otherwise, the effort will pull the arm from the arm.

An alternative configuration is to round up the arm. However, it may still require a bearing to prevent the arm from falling to the ground.

#### Third class lever examples

With third-class levers, the effort is between the load and the fulcrum, for example in barbecue tongs. Other examples of third-class levers are a broom, a fishing rod, and a woomera.

• Tweezers
• Stapler
• Mousetrap
• Broom
• Hockey stick

There are three types or classes of levers, where load and effort are located in relation to the fulcrum. The first-class levers are an integer between effort and load. The second-class levers are loaded between effort and fulcrum. And the third-class levers are between load and fulcrum.

## Uses of Lever

A lever usually is used to move or lift objects. Sometimes it is used to push against objects, but not actually move them. Levers can be used to exert a large force over a small distance at one end by exerting only a small force over a greater distance at the other.

Uses of Lever:

• Levers make it easy to lift heavy materials, remove tight objects, and cut objects.
• Hammer claws are common levers that help you remove nails embedded in wood or other hard surfaces.
• Wheel bars are helpful every day because they allow you to transport loads that are too heavy or heavy.
• Tweezers and tweezers are examples of levers that make it easy to lift or remove items, even if the items are not heavy.
• Scissors are an example of a lever that uses force to cut or separate material.

## FAQ

A lever is a simple machine consisting of a beam or rigid rod pivoted at a fixed hinge, or fulcrum. A lever is a rigid body capable of rotating on a point on itself. On the basis of the locations of fulcrum, load and effort, the lever is divided into three types.

It has been found by experiment that two equal forces acting in opposite directions, i.e., clockwise and counterclockwise, and applied to a uniform lever at equal distances from the fulcrum counteract each other and establish a state of equilibrium, or balance, in the lever.

There are three types of levers: first-class, second class, and third class. The difference between the three classes depends on where the force is, where the fulcrum is and where the load is.

First-class levers have the fulcrum between the force and the load. In summary, in a first-class lever, the effort (force) moves over a large distance to move the load a smaller distance, and the fulcrum is between the effort (force) and the load.

In second class levers, the load is between the effort (force) and the fulcrum. A common example is a wheelbarrow where the effort moves a large distance to lift a heavy load, with the axle and wheel as the fulcrum. In a second class lever, the effort moves over a large distance to raise the load a small distance.

In the third-class levers, the effort is between the load and the fulcrum, for example in barbecue tongs. Other examples of third-class levers are a broom, a fishing rod, and a woomera.