Question

State True or False.

High pressure and low voltage should be maintained in the discharge tube for the production of cathode rays.

• A. True
• B. False

Answer 1

The correct option is B False

It is a false statement.
Pressure has to be low because an electron is a very lightweight subatomic particle. It weighs about 1/1836th as much as a single proton, so any gas atoms that are in the flight path of an electron will cause it to scatter. That means we need to pump all the air out of the inside of the tube. After we remove all we can, we fire a "getter" (a chemical coated onto a small area inside the tube) which will bind any remaining gas molecules left inside the tube to complete the evacuation process. High voltage has to be maintained to increase the kinetic energy of an electron so that it can hit the target at very high speed.