Question

The property of cathode rays used in the monitor of a computer is :

• A. high velocity of the rays
• B. high ionization power of the rays
• C. the property to cause fluorescence
• D. rectilinear propagation

Answer 1

The correct option is C the property to cause fluorescence

A CRT monitor contains millions of tiny red, green, blue phosphor dots that glow when struck by an electron beam that travels across the screen to create visible image.

This is called Fluorescence, this is shown in above diagram:

In CRT tube cathode is heated filament. The heated filament is in a vacuum created inside a glass tube. The stream of electrons generated by an electron gun is powered out of cathode and is attracted to anode. This screen is coated with phosphor, an organic material that glows when struck by electron beam. This process is called fluorescence.