What is the point mass? Give the examples.

Explanation

(i) The mass of any object be assumed to be concentrated at a point.
(ii) Then this idealized mass is called "point mass".
(iii) Term "point mass" is a relative term. It has meaning only with respect to a reference frame and with respect to the kind of motion that we analyse.
Examples :
1. To analyse the motion of Earth with respect to Sun, Earth can be treated as a point mass.
2. If we throw an irregular object like a small stone in the air, to analyse its motion, it is simpler to consider the stone as a point mass as it moves in space.