In the surrounding of a point
charge when a unit point mass is brought from infinity to any point work done
is calculated by line integral of gravitational field within limits from
infinity to that point. This work will be the gravitational interaction energy
of a unit mass or the gravitational potential at that point. To understand the
analysis see the video below
Work Done in Gravitational Field:
If we know the gravitational potential in space at a point V then the work done
in bringing a mass m from infinity to this point is given as mV which is also
the gravitational interaction energy of the point mass at that point. So if in
a region of space if a mass m is transported from one point to another the work
done in this displacement can be directly calculated by finding the difference
in gravitational potential energy. To understand this analysis see the video
below –