A metal having a work function of 2.8 eV is illuminated with monochromatic light whose photon energy is 3.9 eV. What is the threshold frequency for photoelectron production? (h = 6.626 × 10^-34 J ∙ s, 1 eV = 1.60 × 10^-19 J) A) 6.8 × 10¹⁴ Hz B) 2.7 × 10¹⁴ Hz C) 7.6 × 10¹⁴ Hz D) 8.5 × 10¹⁴ Hz E) 9.4 × 10¹⁴ Hz

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Quizplus · Accepted Answer

The threshold frequency is given by the equation:$$f_0 = \frac{\phi}{h}$$where:$$f_0$$ is the threshold frequency$$\phi$$ is the work function$$h$$ is Planck's constantSubstituting the given values into the equation, we get:$$f_0 = \frac{2.8 	ext{ eV}}{6.626 	imes 10^{-34} 	ext{ J s}} 	imes \frac{1.60 	imes 10^{-19} 	ext{ J}}{1 	ext{ eV}} = 6.8 	imes 10^{14} 	ext{ Hz}$$Therefore, the correct answer is A.

A Metal Having a Work Function of 2