Four charges $ + Q,\, – Q,\, + Q,\, – Q$ are placed at the corners of a square taken in order. At the centre of the square

A solid conducting sphere having a charge $Q$ is surrounded by an uncharged concentric conducting hollow spherical shell. Let the potential difference between the surface of the solid sphere and that of the outer surface of the hollow shell be $V$. If the shell is now given a charge of $-3Q$, the new potential difference between the same two surfaces is……$V$

Find the equation of the equipotential for an infinite cylinder of radius ${{r_0}}$, carrying charge of linear density $\lambda $.

Uniform electric field of magnitude $ 100$ $V/m$ in space is directed along the line $y$ $=$ $3$ $+$ $x$. Find ………$V$ the potential difference between point $A (3, 1)$ $ \&$ $ B$ $ (1, 3)$

A thin spherical insulating shell of radius $R$ carries a uniformly distributed charge such that the potential at its surface is $V _0$. A hole with a small area $\alpha 4 \pi R ^2(\alpha<<1)$ is made on the shell without affecting the rest of the shell. Which one of the following statements is correct?