Two charges 5 × 10-8 C and -3 x 10-8 C are located 16 cm apart from each other. At what point (s) on the line joining the two charges is the electric potential zero? Take the potential at infinity to be zero
Let p be the point of zero potential be p at distance r from the charge 1.. d=16 cm Electric potential, v=q1/4πϵor+q2/4πϵo(d−r) for v=0, rq1=−d−rq2 ⇒r5×10−8=0.16−r−3×10−8 r=10 cm If, point p is outside, v=q1/4πϵor+q2/4πϵo(r−d) so here, r=40 cm
