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**Magnitude of "q" ~ What am I doing wrong?**

## Homework Statement

This is my homework problem:

"Two equal charges are separated by 3.7 x 10^-10 m.

The force between the charges has a magnitude of 2.37 x 10^-3 N. What is the magnitude of q on the charges?"

## Homework Equations

F(electricity) = k(Coulomb)(q1 • q2)/r^2

E = F(e)/q0

E = k(C) • q/r^2

...I can't really seem to think of any other relevant equations for this particular problem, though I have a lot of others that go along with this electricity unit in Physics. If you can think of some that apply that I missed, please let me know. :)

## The Attempt at a Solution

Here's my insanity work below, hahaha. I tried two approaches and got the same answer, but I still don't think it's correct:

(a)

F = kc(q1q2/r^2)

2.37 x 10^-3 = 8.99 x 10^9 • q1q2 / (3.7 x 10^-10)^2

F • r^2 = kc • q1q2

F • r^2 / kc = q1q2

2.37 x 10^-3 • (3.7 x 10^-10)^2 / 8.99 x 10^9 = q1q2

q1q2 = 3.61 x 10^-32

(b)

E = kc • q/r^2

2.37 x 10^-3 = 8.99 x 10^9 • q/(3.7 x 10^-10)^2

2.37 x 10^-3 / 8.99 x 10^9 = q/(3.7 x 10^-10)^2

2.37 x 10^-3 / 8.99 x 10^9 • (3.7 x 10^-10)^2 = q

q = 3.61 x 10^-32

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Please help me. I don't really know what I'm doing wrong, or if I'm doing anything wrong. I have a feeling I got this incorrect, however. Also, I don't exactly understand the concept of "q". I know what q1 and q2 are, but if anyone could explain it just one more way (I've already heard it three different approaches, but I still don't comprehend), I'd be much obliged for any input as soon as possible. Thank you! :)