If Neptune’s mass were reduced, what could be done to maintain the same force of gravitational attraction between Neptune and the Sun?

Neptune and the Sun would need to move farther apart.

Explanation:

The equation for gravitational force is F = Gm1m2/d2 where G is the gravitational constant, m1 and m2 are the masses of the bodies in question, and d is the distance between the two.

Since the masses are proportional to the distance, if the mass of one body is reduced, the distance between them must also be reduced in order to keep the same gravitational force between them.

the electric field is a “force field” around a charged object that illustrates the direction the electric force would push an imaginary 

force required to detach it is given by

charges are taken to be fundamental charge

now we have

so above is the minimum distance at which it will detach