Answer: work function φ.
- A work function φ
- B photon energy hν
- C photon count
- D value zero
Correct answer: A. work function φ
Explanation: KE_max = hν − φ, where φ is the work function of the metal.
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.