Question

The charge on a conductor is positive Q and its potential is V
(i.e. the electric potential on its surface)
If some more positive charge is added to it, what are the possible values of its new potential?

• A. $\frac{3V}{2}$
• B. $\frac{2V}{3}$
• C. $\frac{5V}{6}$
• D. $\frac{4V}{3}$

Answer 1

Answer: (A), (D)

The correct options are
A $\frac{3V}{2}$
D $\frac{4V}{3}$

For any isolated conductor we have learned that Q is directly proportional to V. So as Q increases V must increase. Now since we don’t know the shape of the conductor we can’t say to what exact value V would increase to. But we can be sure of one thing - that it will increase!! So in the given options the possible values are either $\frac{3V}{2}or\frac{4V}{3}$. Other values are less than the initial potential V.