Answer: frequency.
- A frequency
- B wavelength
- C speed
- D mass
Correct answer: A. frequency
Explanation: E = hν, so photon energy increases with frequency.
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.