An electron is moving towards the $x$-axis. If an electric field is applied along the $y$-direction,what is the path of the electron?

Two long parallel plates $A$ and $B$ are separated by a distance of $4 \ cm$ with an electric field of $45.5 \ Vm^{-1}$ between the plates directed normally from plate $A$ to plate $B$,as shown in the figure. An electron is projected from plate $A$ with velocity $v$ at an angle of $30^{\circ}$ with the surface of plate $A$. The maximum value of $v$ so that the electron does not hit plate $B$ is (Assume gravity-free space,charge of electron $= 1.6 \times 10^{-19} \ C$ and mass of electron $= 9.1 \times 10^{-31} \ kg$): (in $km \ s^{-1}$)

$A$ simple pendulum has a bob with mass $m$ and charge $q$. The pendulum string has negligible mass. When a uniform and horizontal electric field $\vec{E}$ is applied, the final tension in the string changes. The final tension in the string, when the pendulum attains an equilibrium position, is . . . . . . . ($g$: acceleration due to gravity)

An electron of mass $m_e$ initially at rest moves through a certain distance in a uniform electric field in time $t_1$. $A$ proton of mass $m_p$ also initially at rest takes time $t_2$ to move through an equal distance in this uniform electric field. Neglecting the effect of gravity,the ratio of $t_2/t_1$ is nearly equal to

The acceleration of an electron in an electric field of magnitude $50\, V/cm$ is (given that the $e/m$ ratio of the electron is $1.76 \times 10^{11}\, C/kg$):

In Millikan's experiment,an oil drop having charge $q$ becomes stationary upon applying a potential difference $V$ between two plates separated by a distance $d$. The weight of the drop is