Question

If the pressure within a discharge tube is reduced from ${10}^{-3}mm$ to ${10}^{-4}mm$ mercury then the rays which are produced perpendicular to the cathode surface are known as

• A. Anode rays
• B. Cathode rays
• C. X-rays
• D. Canal rays

Answer 1

The correct option is B Cathode rays

If the pressure in a discharge tube is reduced to ${10}^{-4}mm$, then cathode rays (rays of electrons) come out, perpendicular to the cathode surface .Due to very low pressure, electrons can easily reach to the target without any deflection due to gas molecules.

Anode rays or Canal rays travel from anode through the cathode holes to the tube wall.

X-rays are generated by the reverse photo electric effect, in which photons are produced by electrons.