Jan 2023

Understanding Momentum In IP Physics: What Actually Is It?

January 26, 2023
Understanding Momentum In IP Physics: What Actually Is It?


Many IP students consider physics one of the most challenging subjects to learn. Indeed, numerous students sign up for IP Physics tuition in Singapore to further understand their lessons and catch up with the requirements of IP Physics. With that said, Physics is one of the most interesting subjects too. It allows students to understand how the world and the universe work on a deeper level.

In IP Physics, there are so many lessons about the world to pique your interest and stimulate your critical thinking abilities. One of them is the lesson on momentum. You have probably already heard of it, but many are still unsure about what it means. In this article, we briefly explore the concept of momentum and its relevance to the study of Physics.

What is Momentum in Physics?

Momentum is defined as a measurement of mass in motion. Any moving object has momentum. In Physics, particularly, the momentum of an object is equal to its mass times the velocity (mass x velocity = momentum).

Being a derived quantity calculated by multiplying the mass with the velocity, momentum always has a direction, which is the same as the velocity of the object’s motion. Momentum is commonly abbreviated using the letter “p.” Hence, the equation for momentum is p = m x v, where m is the mass, v is the velocity, and p is the momentum.

Conservation of Momentum

Momentum is a conserved quantity. This is one of the essential properties of momentum and the reason why it is so significant in the study of Physics. Being a conserved quantity, the overall momentum of a particular system will always remain the same, regardless of what changes the system undergoes (that is, as long as there is no introduction of new momentum-carrying objects).

The main reason momentum is so significant in Physics is that it enables physicists to come up with the measurements of the system before and after the system change and formulate conclusions about it without having to know every detail of the collision.

A classic example of this is the collision of two billiard balls. This kind of collision is referred to as an elastic collision. To determine what is going to occur after the collision, you can calculate the two balls’ momentum prior to the collision (p1i and p2i, where the letter “I” means “initial”). Their sum will be the overall momentum of the system (PT, where the letter “T” means “total”), and the overall momentum will be equal to this after the collision.

Ultimately, after the collision, the momenta of the two billiard balls will be p1f and p1f, where the letter “f” means “final.” This leads to the equation: p1i + p2i = p1f + p1f = pT.

Aside from elastic collision, there is another kind of collision in Physics called an inelastic collision. It is characterised by the fact that during the collision, there is a loss of kinetic energy, typically in the form of sound and heat. However, in an inelastic collision, there is a conservation of the momentum so that the overall momentum after the collision equals the overall momentum, just as in the case of an elastic collision.

Furthermore, when two objects stick together due to a collision, there is now the so-called perfectly inelastic collision since here, the maximum amount of kinetic energy has been lost. A great example is when a bullet is fired into a block of wood. The bullet halts in the wood, and the two objects used to move become one. This results in the equation: m1v1i + m2v2i = (m1 + m2)vf.

Some of these quantities in the equation can be used to calculate the other quantities. Therefore, you can shoot the block of wood, determine the velocity at which the block of wood moves when being shot, and then identify the momentum (and velocity) at which the bullet was moving before the collision.


Overall, momentum may be a bit challenging to understand initially, but it is also one of the most exciting lessons you will probably come across in your study of IP Physics. Suppose you need help comprehending the different mathematical terms or equations involved in learning momentum. In that case, you can always seek the assistance of a Physics tutor in Singapore to help you in your study.

Tuition Physics is the tuition centre you can count on for the most extensive and effective Physics tuition class in the country! We have the most knowledgeable and reliable physics tutors who can help you understand and master every lesson you are struggling with. Feel free to contact us to learn more about our tuition classes or to sign up for one today.

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