An electron and a proton are in a uniform electric field, the ratio of their accelerations will be

A simple pendulum is suspended in a lift which is going up with an acceleration $5\ m/s^2$. An electric  field of magnitude $5 \ N/C$ and directed vertically upward is also present in the lift. The charge of the bob is $1\ mC$ and mass is $1\ mg$. Taking $g = \pi^2$ and length of the simple pendulum $1\ m$, the time period of the simple pendulum is ......$s$

An electron enters in an electric field with its velocity in the direction of the electric lines of force. Then

An electron is rotating around an infinite positive linear charge in a circle of radius $0.1 \,m$, if the linear charge density is $1 \,\mu C / m$, then the velocity of electron in $m / s$ will be ...... $\times 10^7$

In Millikan's oil drop experiment, a charged drop falls with terminal velocity $V$. If an electric field $E$ is applied in vertically upward direction then it starts moving in upward direction with terminal velocity $2V$.If magnitude of electric field is decreased to $\frac{E}{2}$, then terminal velocity will become

A uniform electric field $\vec E$ exists between the plates of a charged condenser. A charged particle enters the space between the plates and perpendicular to $\vec E$ . The path of the particle between the plates is a