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Impulse Formula

Last updated date: 23rd May 2024
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Impulse Definition and Formula

The term pulse in physics has the purpose of describing or quantifying the effect of a force acting overtime on an object to alter its momentum. It is usually represented by the symbol J and expressed in Newton seconds or kilograms per second.  

There is nothing more common than seeing delicate items like glass products wrapped in newspaper, or ordered purchases packed in air-bubbled plastic sheets.     


Increasing the impulse (product remains undamaged) decreases the downward force on the object over time, since the impulse increases.

A force is inversely proportional to an impulse. In other words, the magnitude of the impulse formula is dependent on the force and time change. We will discuss the impulse formula in this article.


In sports, the concept of momentum is common. When a commentator describes a player as having momentum, they are referring to the fact that the player is actually in motion and very difficult to stop. Since bodies that move with momentum can't be stopped, it is imperative to apply a force for a specified duration against their direction of motion. As the momentum increases, stopping them becomes increasingly difficult. The body must be brought to a halt with more force and for a longer period of time. The body's velocity and momentum change when a force acts on it for a specified period of time.

An object's velocity can be changed in either direction by a force. The momentum may also change if the object's velocity changes.

The Impulse Formula of Physics

Let's take a closer look at the impulse formula:

All delicate items should be rolled in the newspaper or wrapped in air-bubbled plastic sheets, as discussed in the impulse formula topic mentioned above. Due to the fact that the item accidentally falls on the ground, the force will first reach the rolled newspaper before reaching the item.

In terms of downward force, we observe that it was most noticeable when it hit the newspaper/effect, and gradually decreased once it reached the item. Time, therefore, increases in this scenario. Thus, the force effect decreases with time.

The magnitude of impulse has been found to increase with time; however, the effect of force has been demonstrated to decrease with time and impulse. Here is an example of an impulse equation:

Impulse Equation

J = F. Δt…(1) (It is the required Linear Impulse Formula)

Here we have,  

The impulse ‘J’ is directly proportional to time and inversely proportional to the force being subjected.

We measure impulse ‘J’ in N.s. Next, we will study impulse ‘J’ in its dimensional form.

Dimensional Formula of Impulse 

As we know, the equation for impulse physics is:

J = F.Δt


This dimension is measured in Newtons and has a formula of [M1L1T-1].

Δt is measured in seconds and has the dimensional formula [M0L0T1]. 

If we add the values of equations (2) and (3) to equation (1), the dimensional formula of impulse is as follows:

              = [M1L1T-2] * [M0L0T1]

The following dimensional formula is obtained by solving the above equation:

The required dimension for the impulse formula is [M1L1T-1].

Equation of Impulse Momentum

To calculate Impulse, use the following equation: 

J = m * Δv

In simple words,

Impulse = mass (m) * (Velocity2-Velocity1)

There are two points in time where velocity1 & velocity2 represent movement at different speeds. This is referred to as velocity change.

Using the equation above, we can calculate the unit of impulse as follows:

Mass = in kg

Velocity = in m/s

J   = kg . m/s or N.s 


For the following equations, both the dimensional and unit formulas remain the same:

  • J = F * Δt   

  • J = m * Δv

Delicate items are protected by an impulse against external force.    

FAQs on Impulse Formula

1. Can you give some examples of impulses?

The following are some examples of impulses:

  • The damage suffered by someone falling from a bed to a floor is greater than if the person fell onto a pile of sand. As a result, the contact time increases, and the force effect is reduced since the sand yields more than the cemented floor.

  • A nylon rope is also used for rock climbing for the same reason. Climbers attach themselves to rock faces using nylon ropes. Losing her hold on the rock will cause a rock climber to tumble. As a result, the rope in this case will slow her speed eventually, preventing a dangerous fall to the ground below.

2. What are human impulses?

According to biology, a neuron sends electrical signals along its axon. A neuron's activity can stimulate or inhibit the activity of other neurons or tissues within the body. As an impulse, a person might eat chocolate or listen to a song out of the blue.

3. How do impulses and impulses of force differ?

A force that acts impulsively on an object is a force that acts for a short duration. It is mostly an impulsive force that is produced during a collision with one or more objects that result in a change in velocity or momentum. Impulses, on the other hand, are the result of an impulsive force acting over a short period of time. They represent the change in momentum brought about by a sudden force.

4. How do you define linear momentum?

It is defined as a vector quantity, as it is the product of mass and velocity, and provides us with the measure of mass in motion.

The equation is as follows:

                         p = mv

In this case, p is the linear momentum of an object in kilograms/second. Parallel to the object's velocity, the direction of linear momentum remains unchanged.