In the photoelectric effect, what happens to the maximum kinetic energy of emitted photoelectrons when the intensity of incident light is doubled?
Answer and explanation
Correct answer: C. It remains strictly unchanged
- Step 1: Einstein's equation is E_k(max) = hf - phi, where phi is the work function of the metal. Step 2. Increasing intensity increases the number of photons per second, not the energy of individual photons. Answer: It remains strictly unchanged. Why not the others:* Higher intensity increases the photocurrent (electrons emitted per second), but not their individual energy.
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