The electric field inside a spherical shell of uniform surface charge density is

A body having specific charge $8\,\mu {C} / {g}$ is resting on a frictionless plane at a distance $10\, {cm}$ from the wall (as shown in the figure). It starts moving towards the wall when a uniform electric field of $100 \,{V} / {m}$ is applied horizontally toward the wall. If the collision of the body with the wall is perfectly elastic, then the time period of the motion will be $....\, S.$

In an ink-jet printer, an ink droplet of mass $m$ is given a negative charge $q$ by a computer-controlled charging unit, and then enters at speed $v$ in the region between two deflecting parallel plates of length $L$ separated by distance $d$ (see figure below). All over this region exists a downward electric field which you can assume to be uniform. Neglecting the gravitational force on the droplet, the maximum charge that can be given so that it will not hit a plate is close to :

A proton and an $\alpha$-particle having equal kinetic energy are projected in a uniform transverse electric field as shown in figure

A particle of charge $1\  \mu C\  \&\  mass$ $1\  gm$ moving with a velocity of $4\  m/s$ is subjected to a uniform electric field of magnitude $300\  V/m$ for $10\  sec$. Then it's final speed cannot be.......$m/s$

A charged particle of mass $m$ and charge $q$ is released from rest in a uniform electric field $E.$ Neglecting the effect of gravity, the kinetic energy of the charged particle after ‘$t$’ second is