$A$ sphere of radius $1\,cm$ has a potential of $8000\,V$. The energy density near its surface will be:

Two charges $5 \times 10^{-8} \; C$ and $-3 \times 10^{-8} \; C$ are located $16 \; cm$ apart. At what point$(s)$ on the line joining the two charges is the electric potential zero? Take the potential at infinity to be zero.

The electric potentials at two points $P$ and $Q$ are $10 \ V$ and $-4 \ V$ respectively. The work done in moving $100$ electrons from $P$ to $Q$ is:

Three equal charges are placed at the corners of an equilateral triangle. Which of the graphs below correctly depicts the equally-spaced equipotential surfaces in the plane of the triangle? (All graphs have the same scale.)

$A$ regular hexagon of side $10 \text{ cm}$ has a charge of $1 \mu\text{C}$ at each of its vertices. The potential at the centre of the hexagon is $\left[\frac{1}{4 \pi \varepsilon_0} = 9 \times 10^9 \text{ SI unit}\right]$.

The electric potential at the centre of two concentric half rings of radii $R_1$ and $R_2$,having the same linear charge density $\lambda$,is $(\varepsilon_0 = \text{permittivity of free space})$