Question

What is a point mass?

Answer 1

It is a entity considered in derivations or solving of questions, generally in physics.
In the theory of gravity, physicists often discuss a point mass, meaning a pointparticle with a nonzero mass and no other properties or structure. Likewise, in electromagnetism, physicists discuss a point charge, a point particle with a nonzero charge.

So basically it is a concentrated mass of required amount with almost zero geometric dimension.

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