A photon of wavelength 200 nm strikes the surface of a metal causing an electron to be ejected with kinetic energy of 4.3 x 10-19 J. What was the threshold frequency of the metal?

Question

Question 8 options:

1.2 x 1013 Hz

8.5 x 1014 Hz

7.4 x 1015 Hz

1.6 x 1012 Hz

5.2 x 1015 Hz

Answer 1

After you plug everything in, you'll find the answer is 8.5 x 10¹⁴ Hz. You should practice photoelectric effect questions that give you different variations of input information. For example, what if you know the work function and the frequency of the incoming photon. Would you know how to find the KE of the ejected electron? What about the speed of the electron?

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