Question

A point charge $q$ is placed at distance $a$ from the centre of an uncharged this spherical conducting shell of radius $R=2a$. A point $P$ is located at a distance $4a$ from the centre of the conducting shell as shown. The electric potential due to induced charge on the inner surface of the conducting shell at point $P$ is

• A. $\frac{kq}{5a}$
• B. $-\frac{kq}{5a}$
• C. $\frac{kq}{4a}$
• D. $-\frac{kq}{4a}$

Answer 1

The correct option is A $\frac{kq}{5a}$

Point charge $=q$

radius $=R=2a$

$P$ is located at a distance $=4a$

The electric potential due to induced charge on the inner surface of the coaching shell at point $P$, $P=K\frac{q}{5a}$

Which is defined by the value of the $R=2a$ negative sign due to opposite direction.