<P> A point particle (ideal particle or point - like particle, often spelled pointlike particle) is an idealization of particles heavily used in physics . Its defining feature is that it lacks spatial extension: being zero - dimensional, it does not take up space . A point particle is an appropriate representation of any object whose size, shape, and structure is irrelevant in a given context . For example, from far enough away, any finite - size object will look like and behave as a point - like object . </P> <P> In the theory of gravity, physicists often discuss a point mass, meaning a point particle 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 . </P> <P> Sometimes, due to specific combinations of properties, extended objects behave as point - like even in their immediate vicinity . For example, spherical objects interacting in 3 - dimensional space whose interactions are described by the inverse square law behave in such a way as if all their matter were concentrated in their centers of mass . In Newtonian gravitation and classical electromagnetism, for example, the respective fields outside a spherical object are identical to those of a point particle of equal charge / mass located at the center of the sphere . </P>

Where are electrons located what is the charge for this particle