Question

A non conducting ring of radius $0.5m$ has charges of $1.11\times {10}^{-10}$ distributed non-uniformly on its circumference. An electrical field is spread everywhere in space. The value of the potential at he centre of the ring is (approximately):

• A. zero
• B. $1V$
• C. $2V$
• D. $4V$

Answer 1

The correct option is C $2V$

Since, the distance of any small charge element $dq$ on ring is at a distance $0.5m$ from the centre. Potential due to this element is $dV=\frac{kdq}{R}$.

Hence, potential due to entire ring is :

$V=\int dV=\frac{k}{R}\int dq=\frac{kQ}{R}=\frac{9\times {10}^9\times 1.11\times {10}^{-10}}{0.5}=2V$