In the electric field of a point charge $q$, a certain charge is carried from point $A$ to $B, C, D$ and $E$. Then the work done

Consider a system of three charges $\frac{\mathrm{q}}{3}, \frac{\mathrm{q}}{3}$ and $-\frac{2 \mathrm{q}}{3}$ placed at points $\mathrm{A}, \mathrm{B}$ and $\mathrm{C}$, respectively, as shown in the figure,

Take $\mathrm{O}$ to be the centre of the circle of radius $\mathrm{R}$ and angle $\mathrm{CAB}=60^{\circ}$

Figure:$Image$ 

In a hydrogen atom, the electron and proton are bound at a distance of about $0.53\; \mathring A:$

$(a)$ Estimate the potential energy of the system in $eV$, taking the zero of the potential energy at infinite separation of the electron from proton.

$(b)$ What is the minimum work required to free the electron, given that its kinetic energy in the orbit is half the magnitude of potential energy obtained in $(a)?$

$(c)$ What are the answers to $(a)$ and $(b)$ above if the zero of potential energy is taken at $1.06\;\mathring A$ separation?

Electric field at a place is $\overrightarrow {E\,}  = {E_0}\hat i\,V/m$ . A particle of charge $+q_0$  moves from point $A$ to $B$ along a circular path find work done in this motion by electric field 

The work done in moving an electric charge $q$ in an electric field does not depend upon

When a proton is accelerated through $1\,V$, then its kinetic energy will be.....$eV$