In an electron gun, the electrons are accelerated by the potential $V$. If e is the charge and $m$ is the mass of an electron, then the maximum velocity of these electrons will be
$\frac{{2eV}}{m}$
$\sqrt {\frac{{2eV}}{m}} $
$\sqrt {\frac{{2m}}{{eV}}} $
$\frac{{{V^2}}}{{2em}}$
In Millikan’s oil drop experiment, an oil drop of mass $16 \times {10^{ - 6}}kg$ is balanced by an electric field of ${10^6}V/m.$ The charge in coulomb on the drop, assuming $g = 10\,m/{s^2}$ is
An electron (charge =$1.6 \times {10^{ - 19}}C$) is accelerated through a potential of $ 100,000 V$. The energy acquired by the electron is
Which scientist invented cathode rays ?
Positive rays consists of
The fact that electric charges are integral multiples of the fundamental electronic charge was proved experimentally by