Answer: 2.0.
- A 1.5
- B 2.0
- C 1.67
- D 2.5
Correct answer: B. 2.0
Explanation: Einstein's equation gives Kmax = h(ν - ν0). Initially K1 = h(8 - 5) × 1014 = 3h × 1014. Finally K2 = h(11 - 5) × 1014 = 6h × 1014. Therefore K2/K1 = 2.
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.