$A$ pellet carrying a charge of $0.5\, C$ is accelerated through a potential difference of $2,000\, V$. What is the kinetic energy attained by the pellet?

Figures $(a)$ and $(b)$ show the field lines of a positive and negative point charge respectively.
$(a)$ Give the signs of the potential difference $V_{P}-V_{Q}$ and $V_{B}-V_{A}$.
$(b)$ Give the sign of the potential energy difference of a small negative charge between the points $Q$ and $P$,and $A$ and $B$.
$(c)$ Give the sign of the work done by the field in moving a small positive charge from $Q$ to $P$.
$(d)$ Give the sign of the work done by the external agency in moving a small negative charge from $B$ to $A$.
$(e)$ Does the kinetic energy of a small negative charge increase or decrease in going from $B$ to $A$?

Prove that electrostatic forces are conservative in nature and define electrostatic potential energy.

The electric potential inside a conducting sphere:

$A$ total electric charge $Q$ is distributed on the surface of a sphere of radius $R$. What is the electrical potential energy of this system?

$A$ sphere with charge $Q$ is placed concentrically inside an uncharged spherical shell. The potential difference between them is $V$. Now,if a charge of $-3Q$ is given to the spherical shell,what will be the potential difference between them?