Answer: Photon.
- A Electron
- B Photon
- C Same
- D Depends on mass
Correct answer: B. Photon
Explanation: Photon energy E = hc/lambda. Electron KE = p²/2m = h²/(2m lambda²). Since hc/lambda >> h²/(2m lambda²) for typical wavelengths, photon has more energy.
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.