Two charges 5×10−8C and −3×10−8C are located 0.16m apart. At what point(s) on the line joining the two charges in the electric potential zero? Take the potential at infinity to be zero.
Using the formula for electrostatic potential
we get
Kq1x+Kq2(x−0.16)=0
5x−3x−0.16=0
We get the value of x as
x=40cm
x−r=24cm