Question -
Answer -
There are two charges,
Distance between the two charges, d =16 cm = 0.16 m
Consider a point P on the line joining the two charges,as shown in the given figure.
r =Distance of point P from charge q1
Let the electric potential (V) atpoint P be zero.
Potential at point P is the sum ofpotentials caused by charges q1 and q2 respectively.
Where,
=Permittivity of free space
For V = 0, equation (i)reduces to
Therefore, the potential is zero at a distance of 10 cmfrom the positive charge between the charges.
Suppose point P is outside the system oftwo charges at a distance s from the negative charge, wherepotential is zero, as shown in the following figure.
For this arrangement, potential is given by,
For V = 0, equation (ii)reduces to
Therefore, the potential is zero at adistance of 40 cm from the positive charge outside the system of charges.