Cathode-ray tubes

Definition

Cathode-ray tubes (CRTs) are vacuum tubes that contain one or more electron guns and a phosphorescent screen used to display images. They were instrumental in the discovery of the electron and played a key role in early atomic physics experiments.

5 Must Know Facts For Your Next Test

1. Cathode rays are streams of electrons observed in vacuum tubes.
2. J.J. Thomson used a cathode-ray tube to discover the electron in 1897.
3. Cathode-ray tubes operate by accelerating electrons towards a phosphorescent screen, causing it to glow upon impact.
4. The deflection of cathode rays by electric and magnetic fields provided insights into their negative charge and mass-to-charge ratio.
5. CRTs were pivotal in the development of early television and computer monitors before being replaced by modern technologies.

Review Questions

• What fundamental particle was discovered using a cathode-ray tube?
• How do electric and magnetic fields affect the path of cathode rays?
• What technology did CRTs help develop before being replaced?

Related terms

Electron:

A subatomic particle with a negative charge, discovered by J.J. Thomson using a cathode-ray tube.

Vacuum Tube: An electronic device that controls electric current flow in a high vacuum between electrodes to which an electric potential difference has been applied.

Phosphorescence:

The property of emitting light after exposure to radiation, utilized in CRT screens to display images.