Calculate the work done by the electrostatic force on an electron moving in a circular orbit around the nucleus.

Two equal and opposite charges of masses $m_{1}$ and $m_{2}$ are accelerated in a uniform electric field through the same distance. What is the ratio of their accelerations if the ratio of their masses is $\frac{m_{1}}{m_{2}}=0.5$?

$A$ particle having mass $m$ and charge $q$ is at rest. On applying a uniform electric field $E$ on it,it starts moving. When this particle travels a distance $x$ in the direction of the force,its kinetic energy will be . . . . . . .

$A$ point charge $Q$ is placed in a uniform electric field $\vec{E} = E_1 \hat{i} + E_2 \hat{j}$ at position $(a, b)$. Find the work done in moving it to position $(c, d)$.

Two masses $M_1$ and $M_2$ carry positive charges $Q_1$ and $Q_2$,respectively. They are dropped to the floor in a laboratory setup from the same height,where there is a constant electric field vertically upwards. $M_1$ hits the floor before $M_2$. Then,

When an electron enters an electric field with a velocity in the direction of the electric field lines,then.......