Question

a 20kg ball is at origin and a 10 kg ball is (20cm, 0cm) at what point(s) could a small mass be placed so that the net grav. force =0?

Answer 1

You must specify the object on which you want a net gravitational force of zero.

Answer 2

all of the balls

Answer 3

You cannot zero-out gravitation on them all.

You could put one mass between two other masses and have the net gravitational force = 0, but you can't make the net force on all of them zero.

Answer 4

Oh, phrasing error. Here's the original question...

A 20kg sphere is at the origin, and a 10 kg sphere is at (x,y) =(20cm,0). at what point(s) could you place small mass such that the net gravitational force on it due to the spheres is zero?