In Thomson's experiment if the value of $q/m$ is the same for all positive ions striking the photographic plate, then the trace would be
Straight line
Parabolic
Circular
Elliptical
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
Positive rays consists of
When the speed of electrons increases, then the value of its specific charge
If an electron oscillates at a frequency of $ 1 GHz$ it gives