Two particles are in a uniform electric field whose value is +4000 N/C. The mass and charge of particle 1 are m1 = 1.0x10-5 kg and q1 = -15 µC, while the corresponding values for particle 2 are m2 = 3.0 x10-5 kg and q2 = +35.0 µC. Initially the particles are at rest. The particles are both located on the same electric field line but are separated from each other by a distance d. When released, they accelerate but always remain at this same distance from each other. Find the separation distance.
I used the E1=E2 but i'm stuck on the algebra.