There are several situations of collisions in rigid body dynamics on which different problems are framed.
In such cases we need to conserve angular momentum of the system about a point with respect to
which the net external torque on the body is zero. The most important thing in such cases is to locate a
point in the given system about which angular momentum is to be conserved. With regular practice of
different illustrations only this can be achieved. To understand the applications of concepts in such
situations, watch the illustration videos given below:
https://youtu.be/Kj6TEz423ws
One very important application for rigid body dynamics is the study of a falling rod on a horizontal floor.
There are many concepts are used in analyzing motion of this of rod in situation. To understand the
same, watch the illustration videos given below: