A metal has a work function of 2.3 eV. What is its threshold frequency? (h = 6.63 x 10^-34 J s, 1 eV = 1.60 x 10^-19 J)
Answer and explanation
Correct answer: A. 5.6 x 10^14 Hz
- Step 1: J. Step 2. Hz. Answer: 5.6 x 10^14 Hz. Why not the others: 3.5 x 10^33 Hz forgets to convert eV to joules; 7.5 x 10^14 Hz is the frequency of a 3.1 eV photon; 1.3 x 10^15 Hz is the frequency of a 5.4 eV photon.
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