1. The problem statement, all variables and given/known data A 1.0-C charge is 15 m from a second charge, and the force between them is 1.0 N. What is the magnitude of the second charge? 2. Relevant equations F = k(q1)(q2)/r^2 3. The attempt at a solution F = k(q1)(q2)/r^2 need to solve for q2 so... F(r^2)/k(q1) = q2 1N(225m)/(9x10^9)(1C) = 25nC That is correct, right? I just wasn't sure because this is on my sample exam, but we never used nano numbers during class so I wanted to double check.