Cathode rays are

A stick of $1 \,m$ is moving with velocity of $2.7 \times {10^8}m{s^{ – 1}}$. ……….. $m$ is the apparent length of the stick  $(c = 3 \times {10^8}m{s^{ – 1}})$

The fact that electric charges are integral multiples of the fundamental electronic charge was proved experimentally by

Order of q/m ratio of proton, $\alpha $ -particle and electron is

The ratio of specific charge of an $\alpha $ -particle to that of a proton is