Question

If the force between two fixed Charged spheres is F and you triple the charge on one sphere and also triple the distance between the spheres, what fraction/multiple of original force of attraction is now between the two spheres?

Answer 1

Since the charge has a direct proportionality, the increase will be a factor of three. But, since you triple the distance, which has an inversely squared proportion, it will be 3/9 F or 1/3 F.

*This is all based on the fact that this is true:
$F_s = \frac{Kq_1q_2}{r^2}$