Elementry Electrostatics question 1. The problem statement, all
variables and given/known data Two point charges (q1=+20 nC and
q2=-40 nC) are placed 10.0 cm apart onlong the x-axis. Where can
a third charge (q3=+20 nC) be placed so that the net
electrostatic force on that charge is zero? 2. Relevant
equations 3. The attempt at a solution It's definitely not a
hard problem, I'm guessing I'm supposed to set the entire
equation into equilibrium. Other than that basic concept, I
really don't understand how to solve for this problem. My
professor only went over calculating forces between two charges.
Thanks for any help, I could really use it. :(