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Impulse, Momentum and Energy Forms

For the students who have studied physics in high school, the terms impulse and momentum will not be new to them as most of the mechanics section in the subject of physics comprises this only.

In this article, we will study about the topics of impulse. Momentum and energy forms in very depth and will study everything from the concept to their examples and will finally be leading to the impulse-momentum equation which is only taught if we have studied for the engineering entrance exams. Very often, students tend to get confused between the terms impulse and force. Note that these things have a formula that relates them in every way possible.   

Relation between impulse and force

This means that if we are to derive the formula of impulse then it would come out to be the multiplication of mass and acceleration which in turn has to be multiplied by the time taken for the body to move. So, basically the impulse is the multiplication of force and time. One more thing that is often confused between is the fact that the force that is needed to be taken into consideration is what force. So, the force that is needed to be taken into consideration is the average force that is being applied between the bodies and the time that is to be taken is the time required to move the small body subtracted by the time taken to move the heavy body. 

These two terms are confused in between as most of the things that concern these two are the same including their dimensions. Impulse equals force multiplied by time. This means that if we multiply the force applied on a body  by the time taken to move that body then we will in turn get the impulse applied on the body. Now we know that the term force also has a lot of formulas in it. Some of those formulas are force equals mass multiplied by acceleration.

Everything about impulse 

In this section we will get to know everything about impulse from their units to their vector units. So the SI unit of impulse is the Newton-second which in turn can also be written in the form N-s. 

If we are to understand the concept of impulse, then it is absolutely necessary that this concept in turn involves many terms like acceleration and velocity also and when we are finally doing the last step to calculate the impulse, then it involves the process of integration as well. Now, the process of impulse can also be derived from the impulse applying to the larger or heavier body subtracting the impulse applying to the lighter body. 

Derivation of the impulse momentum equation 

In high school, when mechanics was taught to us we came to know that differentiation of momentum with respect to time gives us force. So this statement forms the basic part of the impulse momentum equation. Note that the force that is calculated is the one which is applied from time t1 to time t2. So, finally when we integrate we find that both the differentiation variables of time cancel each other and we are left with the equation of momentum itself and when we differentiate them from time t1 to time t2. 

We will find that we are left with the equation of mass multiplied by the final velocity minus the initial velocity and this is the impulse momentum equation

Momentum 

Momentum is one of the most basic quantities we learn about when we study physics in higher classes. The formula for momentum is very basic as it is the multiplication of the mass applied to the body multiplied by the velocity with which the body is travelling. Now sometimes in some advanced cases, the time can also be given into the final time and the initial time. The momentum can be applied to various types of particles like the single particle system and the two particle system.

Though the formulas for both these systems are absolutely the same and will remain this way till the time we apply the sign of sigma in front of it. Like, when we consider the two particle system we have to introduce the variables of both mass and velocity like the final and initial mass as well as final and initial velocities. But if we consider the case of one particle system, we have to use both variables only a single time. 

Operations on Momentum 

There are several operations, the algebraic ones like addition, subtraction, multiplication and division. If we want to add, subtract, multiply and divide the momentum of any number of bodies we can just do it like we add, subtract, multiply and divide normal counting numbers. The concept of momentum is normally very easy to understand and can be interesting unless it also includes some complications.   

Conversation of Momentum 

The concept of the conservation of momentum is one of the most important concepts when we have to study about momentum. It includes one more variable than the usual course momentum takes and that variable is called the initial velocity. The reason that it involves initial velocity is because it requires two bodies to be in contact with. 

There are many terms that require the impulse and momentum to be in contact with. Some of those terms include acceleration and this requires the concept of cartesian coordinates as well. 

Conclusion 

The topic of impulse and momentum is very important and they form the basis of the mechanics portion of the physics part. Even though they are easy they should not be dealt with lightly. 

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Why is conservation of momentum important?

Ans : The conservation of momentum is important becaus...Read full

What is the relation between impulse and momentum?

Ans : If we integrate the momentum within the close integrals from the time t2 to t1 and app...Read full

What is impulse?

Ans: Impulse is basically the division of force and time and many other conclusions can also be rea...Read full