According to Newton’s Second Law, the applied force on a body is numerically equal to the rate of change of momentum of the body. Same is valid for center of mass of a system of particles as well. When a force is acting on a body or a system, it changes the momentum of system which is equal to the product of force and the time for which force is acting on the body or system.
This total change in momentum due to the applied force is called Impulse. In other words Impulse can also be given as the momentum imparted by external force/forces acting on a body or a system.
In case of a constant force applied on a body or a system, Impulse can be directly
calculated by product of force magnitude and the time for which force is applied but if the force is
varying with time then we use integration of F.dt within limits from starting to end time of the force
If on a moving body one or more forces are acting for a given duration then we can write the Impulse-
Momentum equation of the body for the given duration.
To understand the applications of Impulse and
its uses in conservation of momentum, see the video – https://youtu.be/bVhMRDZQMF8
The application of Impulse is also useful in variety of problems in which external forces are present and
continuously momentum of a body or the system is changing.
In the section of collisions also impulse
play an important role in analyzing the process of collisions.
To understand some more applications of Impulse, follow the example videos below –