An electron of mass $m$ and charge $e$ is accelerated from rest through a potential difference $V$ in vacuum. Its final velocity will be
$\sqrt{\frac{2 e V}{m}}$
$\sqrt{\frac{e V}{m}}$
$\frac{ eV }{2 m }$
$\frac{e V}{m}$
The mean free path of electrons in a metal is $4 \times 10^{-8} \;m$. The electric field which can give on an average $2 \;eV$ energy to an electron in the metal will be in units of $V / m$
The charge given to any conductor resides on its outer surface, because
Explain electric potential energy. Show that the sum of kinetic energy and electric potential energy remains constant.
Three particles, each having a charge of $10\,\mu C$ are placed at the corners of an equilateral triangle of side $10\,cm$. The electrostatic potential energy of the system is.....$J$ (Given $\frac{1}{{4\pi {\varepsilon _0}}} = 9 \times {10^9}\,N - {m^2}/{C^2}$)
A block of mass $m$ containing a net negative charge $-q$ is placed on a frictionless horizontal table and is connected to a wall through an unstretched spring of spring constant $k$ as shown. If horizontal electric field $E$ parallel to the spring is switched on, then the maximum compression of the spring is :-