Question

Two identical spheres, one positively charged and the other negatively charged are held d cm apart. If the magnitude of the charges on the two spheres is equal, find the electric potential at a point midway on the line joining the centres of the two spheres.

• A. Zero
• B. $10$ V
• C. $5$ V
• D. $1.6$ x ${10}^{-19}V$

Answer 1

The correct option is A Zero

The charge on first sphere be $Q$ and on second sphere is $-Q$.

Now, at point mid-way between spheres, the distance from center of both sphere is equal say $r$.

Net field at the mid point-

$V=\frac{Q}{4\pi {ϵ}_{o}r}+\frac{-Q}{4\pi {ϵ}_{o}r}$

$⟹V=0$

Answer-(A)