A thin conducting ring of radius $R$ is given a charge $+Q$. The electric field at the centre $O$ of

Question

A thin conducting ring of radius $R$ is given a charge $+Q$. The electric field at the centre $O$ of the ring due to the charge on the part $A K B$ of the ring is $E$. The electric field at the centre due to the charge on the part $A C D B$ of the ring is

Professor PC Thomas Classes · Answer

The fields at $O$ due to $A C$ and $B D$ cancel each other. The field due to $C D$ is acting in the direction $O K$ and equal in magnitude to $E$ due to $A K B$.