I need a Physics teacher to help me answer this.?

Question

2 very small spheres are initially neutral and separated by a distance of 0.50 m. Suppose that 3.0 x 10^13 electrons are removed from one sphere and placed on the other..

a) what is the magnitude of the electrostatic force that acts on each sphere?
b) is the force repulsive or attractive?

*formula that i think should be used:
F=kQq / r^2
and
N=q/e

*given:
k = (constant) 8.99 x 10^9 C
r = 0.50m
N = 3.0 x 10^13 (???not sure)
e = (constant) 1.6 x 10^-19

Answer 1

no need for a physics teacher:
the formulas you wrote are right

hint to start solving:
the sphere which lost electrons will be (+ve) charged
with a total charge= q = Ne = 3 x 10^13 x 1.6 x 10^-19 coulomb

the sphere which gained the electrons will be equivalently charged but with negative charge

OK: you have now:

Q = (calculated above)
q = (same one calculated above)
r = given
K = constant

use the first formula you wrote to find force

as for attraction or repulsion, this should be easy, remember that one sphere is +ve and the other is negative charged

Answer 2

I not sure, I am assuming a Physics teacher asked you this question and now you expect one to answer it. That not real good idea. Kinda like going to a Doctor and the first thing he asks is; "What's Wrong"?