Types of Lever

Levers are the simple machine devices, designed to do tasks with minimum effort. A lever improves an input force to produce a higher output force, resulting in leverage. Machines were created and made by humans to reduce human effort. A simple machines is a device that change the direction or magnitude of a force and make the work easier. There are numerous sorts of levers based on the position of the a pivot, force, and weight. Levers help us move things with less effort. By changing the direction or size of the force we apply, they make difficult tasks possible. They’re also used to gain speed or distance in movement.

In this article, we will learn in detail about types of levers along with their example. We will also learn what is lever and how they are classified using mechanical advantage.

What is a Lever?

A lever is a simple machine consisting of a rigid bar or beam that is capable of rotating around a fixed point called a fulcrum. Levers are commonly used to amplify or redirect force, allowing for easier movement or manipulation of objects. Levers are of three types, first class levers, second class levers, and third class levers. Before proceeding to types of levers, let’s learn terms related to levers.

Terms related to a Lever

Terms related to lever are discussed below:

Load (L): Load is a resistive force that has to be overpowered by simple machines. The S.I. unit of Load is Newton (N).

Effort (E): Effort is the external force used to pull off a load on a simple machine. The S.I. unit of effort is Newton (N).

Pivot: It is the support given at a point.

Mechanical Advantage (MA): It is the ratio of the Effort arm to the Load arm. It is given as MA = Effort Arm (E)/Load Arm (L)

Effort Arm: The distance between the effort (force) and the Fulcrum (pivot)

Load Arm: The distance between the Load and the Fulcrum (pivot)

Types of Lever

A lever is a stiff bar that rests on a fixed point with less force. The three different types of levers exist, depending on where the input force, fulcrum, and load are.

• The fulcrum, or fixed point, of a first-class lever is situated between the load and the input force.
• The load on a second-class lever is situated between the input force and the fulcrum, or pivot.
• A lever classified as third-class has the input force positioned midway between the load and the fixed point.

The three class or types of lever are mentioned below:

• First Class Lever
• Second Class Lever
• Third Class Lever

Let’s learn them in detail.

First Class Lever

First Class Lever is a type of lever with the pivot located between the weight and the force generated.

• Its order is denoted as force-fulcrum-weight.
• This is the simplest class of lever.
• When force is applied to one end of the lever, the other end exerts force on the resistance, resulting in a mechanical advantage

Examples of First Class Lever

The examples of first class levers are mentioned below:

Seesaw: A classic example of a first-class lever, where the fulcrum is placed between the applied force (the children sitting on either end) and the resistance (the weight of the children).

Crowbar: When trying open a heavy object like a lid or a door, the fulcrum (the point where the crowbar rests) serves as the pivot, the force is applied at one end of the crowbar, and the resistance is at the other end.

Scissors: In a pair of scissors, the pivot serves as the fulcrum, the force is applied at one handle, and the resistance is encountered at the cutting edge.

Pliers: Pliers work on the same principle as scissors, where the fulcrum is at the joint, the force is applied at one handle, and the resistance is encountered at the jaws, enabling gripping and manipulation of objects.

Second-Class Lever

In second class lever pivot is at one end and the force is applied on the other end.

• The load is situated in the middle of these two.
• The order of this would be pivot-load-force.

Examples of Second Class Lever

The examples of second lever are discussed below:

Wheelbarrow: A wheelbarrow is a second-class lever where the load is placed between the pivot (fulcrum) and the force (handles), allowing for easier lifting of heavy loads.

Nutcracker: In a nutcracker, the nut serves as the fulcrum, the force is applied at one end by squeezing the handles together, and the resistance is the shell of the nut, which breaks due to the applied force.

Bottle Opener: When opening a bottle using a bottle opener, the fulcrum is the edge of the bottle cap, the force is applied at one end of the opener, and the resistance is provided by the cap, which is lifted off.

Door: A door can also be considered a second-class lever, where the hinges act as the fulcrum, the force is applied at the edge of the door handle, and the resistance is encountered at the point where the latch or the door’s weight resists opening.

Third Class Lever

Third Class Lever are the levers in which the fulcrum is at one end and the force is applied in the middle and the weight is on the other end.

• The order is represented as a weight-force-fulcrum.
• In this case, we have to apply more energy to displace the weight to a longer distance

Examples of Third Class Lever

The examples of third class lever are mentioned below:

Tweezers: In tweezers, the fulcrum is the point where the two arms meet, the force is applied at one end by squeezing the handles, and the resistance is encountered at the tips where objects are gripped.

Hockey Stick: In hockey, the stick serves as a third-class lever, with the hands as the fulcrum, the force applied by the player’s hands, and the resistance provided by the puck when striking it.

Shovel: When digging with a shovel, the fulcrum is the point where the shovel blade meets the ground, the force is applied at the handle, and the resistance is the soil being dug.

Fishing Rod: In fishing, the rod acts as a third-class lever, with the hands serving as the fulcrum, the force applied by the angler’s hands, and the resistance provided by the tension of the fishing line when casting or reeling in a fish.

Baseball Bat: A baseball bat can also be considered a third-class lever, with the hands acting as the fulcrum, the force applied by the batter’s hands when swinging, and the resistance provided by the impact with the baseball.

Types of Lever based on Mechanical Advantage

Mechanical advantage is a measure of the effectiveness or efficiency of a machine in amplifying or redirecting force to accomplish a specific task. It quantifies the ratio between the output force or load and the input force or effort applied to the machine. It is given as Mechanical Advantage = Output Force(Load)/Input Force(Effort). The classification of levers based on mechanical advantage is tabulated below:

S. No.	Types Of Lever	Mechanical Advantage	Attribute
1.	First Class Lever	Greater than 1	Force Multiplier
2.	Second Class Lever	Less Than 1	Speed Multiplier
3.	Third Class Lever	Equals to 1	Change in direction of effort

Conclusion

The main use of levers is mechanical advantage which is defined as the quantity a special machine multiplies a force applied. This can be calculated or found out by considering the location of load, effect and fulcrum which in turn gives the type of lever and the amount of mechanical advantage the machine has. When the effort is in a longer distance from the fulcrum then the load becomes easier to move. It is equal to the ratio of the effort of the load and the distance from the effort of fulcrum to the load of the fulcrum’s distance. If the distance of effort to the fulcrum is larger than the load of the fulcrum’s distance then there is a mechanical advantage in the lever. Thus, the ratio of the two distances will be greater than one which means that when there is a long distance from fulcrum to the effort and a short distance from the fulcrum to the load then a small effort will move a heavy or large load.

FAQs on Types of Lever

What is a lever?

A lever is a simple machine that helps us lift or move things with less effort. It has a stick-like part (lever), a point to support it (fulcrum), and the place where we push or pull (force).

How does a lever work?

A lever works by using a pivot point (fulcrum) to help us lift or move heavy things. When we push or pull on one side of the lever, it helps to lift or move the load on the other side.

What are the types of levers?

There are three types of levers namely first-class levers, second-class levers, and third-class levers. They are named based on where the fulcrum, the force, and the load are positioned in relation to each other.

Can you give examples of levers in everyday life?

Examples of levers include seesaws, scissors, pliers, wheelbarrows, and even doors. They all use the same basic idea of using a pivot point to make it easier to lift or move things.

Why are levers useful?

Levers are useful because they help us do work with less effort. They allow us to lift heavier objects or move things more easily by using leverage and mechanical advantage.