Question

The value of e/m for cathode rays

• A. Varies as the atomic number of the element forming the cathode in the discharge tube changes
• B. remains constant irrespective of the nature of gas.
• C. varies as the atomic number of the gas in the discharge tube changes
• D. has the smallest value when the discharge tube is filled with hydrogen

Answer 1

The correct option is B remains constant irrespective of the nature of gas.

The value of e/m is constant irrespective of the nature of gas. It has a value e/ m of $1.75580\times {10}^8$ C/g. It is also independent of the nature of electrodes.