1. Electrons emitted from a material when light or electromagnetic radiation strikes its surface.
Usage: plural form; physics/chemistry term; used in contexts involving the photoelectric effect

Examples

• When ultraviolet light hits the metal surface, photoelectrons are released and can be detected.
• The energy of photoelectrons depends on the frequency of the incident light.
• Scientists measure the kinetic energy of photoelectrons to study the photoelectric effect.
• Photoelectrons ejected from the cathode travel toward the anode in the vacuum tube.
• The number of photoelectrons produced increases with the intensity of the light source.