The color of the positive column in a gas discharge tube depends on:

In $1897$,$J$.$J$. Thomson discovered which particle?

In a discharge tube at $0.02\, mm$ pressure,there is a formation of
[$AIPMT$ $1996$]

For a thermionic emitter (metallic),if $J$ represents the current density and $T$ is its absolute temperature,then the correct curve between $\log_e \frac{J}{T^2}$ and $\frac{1}{T}$ is:

Three particles having their charges in the ratio of $1 : 3 : 5$ produce the same spot on the screen in Thomson's experiment. Their masses are in the ratio of

When a magnetic field is applied in a direction perpendicular to the direction of cathode rays,then their