Calculating energy/work of a quantum

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The energy of a quantum of light with a wavelength of 590 nm is calculated to be approximately 3.37 x 10^-19 J, which converts to 2.11 eV. This energy is insufficient to overcome the work function of a metal with a threshold of 3.0 eV. Therefore, the light will not produce photoelectrons from the metal's surface. The calculations and reasoning provided for both parts of the homework are confirmed to be correct. Feedback indicates that the explanation for part 2 is adequately conveyed.
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Homework Statement



1- Calculate the energy, in joules, of a quantum of light with a wavelength of 590nm.
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2- Will this colour be able to produce photoelectrons from the surface of a metal with a work function of 3.0 eV? Explain your reasoning.

2. Homework Equations

E = hf

v = fλ

3. The Attempt at a Solution

v = fλ

f = v/λ

f = 3.0 x108m/s / 5.9 x10-7m

f = 5.08 x1014HzE = hf

E = (6.63 x10-34J)(5.08 x1014Hz)

E = 3.37 x10-19J

Joules to eVs:

3.37 x10-19J / 3.0 x108mThe quantum will produce 3.37 x10-19 J or 2.11 eV of energy.
2-

As this quantum of energy was determined to have an energy value of 2.11 eV, and the work function of the metal is 3.0eV, then no, this colour will not produce photoelectrons as the energy produced is below the threshold of the metal’s surface.

I am confident in my answers to part 1 but I'm not sure if I explained part 2 correctly or not. Any feedback would be great.
 
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Part 2 is adequately explained.
 
kuruman said:
Part 2 is adequately explained.
Ok thank you
 
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