Photons of energy 3.5 eV fall on a metal with work function 2.0 eV. What is the maximum kinetic energy of the emitted photoelectrons?
Answer and explanation
Correct answer: C. 1.5 eV
- Step 1: Einstein's photoelectric equation: KE max = photon energy - work function. Step 2. KE max = 3.5 - 2.0 = 1.5 eV. Answer: 1.5 eV. Why not the others: 2.0 eV is the work function, 3.5 eV is the photon energy, and 5.5 eV adds the two.
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