Two conducting spheres of the same size have charges q1=-4x10^-6
and q2 = 8x10^-6C,and their centers are separated by 3.0cm
a) what is the force between them?
b) what would be the force if the spheres were touched together and again separated by the same distance
well we could use F=kq1q2/r^2
The Attempt at a Solution
for a) I plugged in 9x10^9 x -4x10^-6 x 8x10^-6 all divided by .09 which gives -3.2 but the answer is -320N.can someone explain my why?
for b) i don't know how it would start.
i tried doing several things. use the -320 as the separated force and
get the force of the one together and add them together.
something like that but i don't know how it gives 40N.