Question

a cathode ray tube is made of glass with a small amount of some kind of gas in it. it has metal electrodes at each end to pick up an electric current. the electrodes are named positive and negative. what are one of the main uses of this device?
○ to speed up the flow of current flowing through a wire
○ to examine a beam of charged particles
○ to magnetize different atoms within a space
○ to change the strength of a proton within an atom

Explanation:

A cathode ray tube (CRT) works by accelerating and deflecting a beam of charged particles (electrons, which are negatively charged). The electrodes create an electric field that accelerates the charged particles. Option 1 is incorrect as CRTs don't speed up current in a wire (they deal with electron beams in a vacuum, not current in a wire). Option 3 is incorrect as CRTs don't magnetize atoms. Option 4 is incorrect as CRTs don't change proton strength. Option 2 is correct because CRTs are used to generate and control a beam of charged particles (electrons) for various applications like in old televisions, oscilloscopes, etc., where the beam of charged particles is examined or used to create images.

Answer:

to examine a beam of charged particles