Who invented $X-$ rays?
Positive rays consists of
Electron volt is a unit of
A cathode emits $1.8 \times {10^{14}}$ electrons per second, when heated. When $ 400\;V$ is applied to anode all the emitted electrons reach the anode. The charge on electron is $1.6 \times {10^{ - 19}}\;C$. The maximum anode current is ............ $\mu A$
In Milikan’s experiment, an oil drop having charge $q$ gets stationary on applying a potential difference $V$ in between two plates separated by a distance $‘d’$. The weight of the drop is
The charge on electron was discovered by