Two carges of + 1.5 x 10 ^-6 C and + 3.0 X 10^-6 C are .20m apart. Where is the electric field between them equal to zero? Do I use the equation Kq2/r^2 ? I also have Kq1q2 / r^2 I am pretty sure the problem can be solved using those two equations, and most likely the first equation Im sorry but I really dont know how to figure this out. I tried to somehow figure it out by finding how much force the first charge is exerting on the second, and vice versa and then subtracting the smaller force from the larger. I dont see how that helps me though. This question is not for marks, I just really need to learn how to do it today for my test tommorow. Please Help!