Sales Toll Free No: 1-855-666-7446

Momentum

Top

Imagine any mass in motion like a bicycle moving, a truck moving, man running etc. what is it that keeps it in moving state? Momentum answers your question.

Momentum can be defined as “mass in motion.” All objects have mass therefore if an object is moving, then it has momentum - it has its mass in motion. It defines force needed to change the momentum which acts for a short time. The larger momentum it is, the greater impulse force is needed. 

What is Momentum?

Back to Top
Very often we hear about Momentum. Its existence is felt in many instances like a car in motion has to be brought to stop by applying the brakes. It can stop by itself if we take off our foot from the accelerator. The car has gained some momentum and it will move even if it’s not accelerated. It justifies that momentum is that which keeps the body in motion.

Momentum depends upon the variables mass and velocity. We can change momentum by changing its mass or changing its velocity, a mass unit is multiplied by a velocity unit to provide a momentum unit. Momentum is a vector measurement of the product of mass and velocity a body has.  It is denoted by p and given as

Momentum Formula
Since the mass is in kg and velocity in ms-1. The momentum unit is kgms-1.

Momentum Formula

Back to Top
Its known that Momentum of a body of mass m and velocity v is given as
Momentum Formula
Using the Newton's second law the force and change of momentum is given asImpulse ForceHere F is the applied force,
dp is the change in momentum,
dt is the time taken.

The force acts for a short time to change the momentum is known as impulse (I). It is the product of force and time as
ImpulseIt is expressed in Newton second (Ns).

Impulse and Momentum

Back to Top
Often we hear people in sports announcing that the team is having momentum, which means that the team is playing with greater force and it’s hard to stop them. Similarly it is factual that each body in motion gains some momentum. The force that is needed to bring it to halt is called Impulse.
Impulse (I) is where greater force (F) is applied on a body for a short time interval t which is given as:

Impulsedp is the change in momentum happening due to the impulse.

Here are some illustrations for it:
  1. A bats man hits the ball with larger force.
  2. A fast moving car hits a wall
  3. A guy kicks a football with larger force.

Linear Momentum

Back to Top
Linear Momentum is momentum gained in a straight line or path. It is closely related to force and is conserved when no external force acts on it. It is the measure of time rate of change of momentum given as
Formula for Linear MomentumThe linear momentum is expressed in kilogram meter per second (kgms-1).
The Angular momentum is the vector measure of the product of body's inertia and velocity in a particular axis for a given rotation.

The rate of change of momentum in a particular angle symbolized as L denoted as
Angular Momentum Formula
It is expressed in Newton meter second (Nms) or kilogram meter square per second (kg m2/s) or Joule second (Js).
→ Read More

Rotational Momentum

Back to Top
Rigid bodies rotates in a a way where all particles in the body move about the same axis with the same angular velocity. We go through many instances in our life like rotation of fly wheel in sewing machine, rotation of satellite around the earth and many more. All these have rotational motions associated with it.

The torque t associated with the motion and is given by

Formula for Torqueor
Torque Formulae

Relativistic Momentum

Back to Top
The momentum used in relativistic mechanics is called Relativistic Momentum. Einstein gave it out. It tells that if a body having rest mass mo traveling with speed v the relativistic mass m associated with it is given by
Relativistic Momentum FormulaHere c is the speed of light. The relativistic mass of a body m is always equal to or greater than the rest mass mo.