Question 1

What is the SI unit of electrostatic potential?

Accepted Answer

The SI unit of electrostatic potential is Volt (V), which is equal to Joule per Coulomb (J/C).

Question 2

Work done in moving a test charge over an equipotential surface is:

Accepted Answer

Work done $W = q \Delta V$. On an equipotential surface, $\Delta V = 0$, so $W = 0$.

Question 3

The electric potential inside a hollow charged spherical conductor of radius $R$ carrying charge $Q$ is:

Accepted Answer

Electric field inside a hollow charged conductor is zero. Therefore, potential remains constant throughout the interior and is equal to its value at the surface, i.e., $V = \frac{1}{4\pi\varepsilon0} \frac{Q}{R}$.

Question 4

When a dielectric slab of dielectric constant $K$ is completely inserted between the plates of a parallel plate capacitor, its capacitance becomes:

Accepted Answer

Capacitance with dielectric $C = K C0$, where $C0$ is capacitance without dielectric. Hence, it increases by $K$ times.

Question 5

The electrostatic potential energy stored in a charged capacitor of capacitance $C$ charged to a potential $V$ is given by:

Accepted Answer

The energy stored in a capacitor is given by $U = \frac{1}{2} C V^2$.

Electrostatic Potential and Capacitance — CBSE Class 12 Physics Important Questions & Revision Notes