Answer: electrons.
- A electrons
- B protons
- C neutrons
- D photons
Correct answer: A. electrons
Explanation: Incident light ejects electrons from the metal in the photoelectric effect.
In the photoelectric setup, light striking the metal plate ejects electrons that cross the evacuated tube to the collector, producing a measurable current on the ammeter.
Concept context
Photoelectric effect, de Broglie waves, Bohr's model, atomic spectra.