Two similar gold spheres both have a charge of q. The centers of the
spheres are separated by a
distance of r. Which of the following would result on the spheres if
you multiplied Force (F) by two?
A. One q would be doubled and r would remain the same.
B. Both q's and r would be doubled.
C. One q would be doubled and r would be doubled.
D. Both q's would be doubled and r would remain the same,

A.One q would be doubled and r would remain the same.

Explanation:

As we know by Coulomb's law of electrostatic force is given as

As we know that the distance between the two charges is given as r

and the two charges are given as q1 and q2

so from above equation we can say that if we double either of the charge then the electrostatic force will double

so we have

so we have

So correct answer will be

A.One q would be doubled and r would remain the same.