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Homework Statement
The American physicist Robert A. Millikan (1868-1953) won the 1923 Nobel Prize in physics, in part for his work on the photoelectric effect. Assume that Millikan observed for a hypothetical metal a maximum kinetic energy of 0.535 eV when electrons were ejected with 431.7 nm light. When light of 258.6 nm was used, he observed a maximum kinetic energy of 2.52 eV. Using these results, calculate the work function, W0, for the metal, without knowing the value for Planck's constant.
Homework Equations
Vo = [(h/e)*f]-(θ/e)
where θ is the work function.
The Attempt at a Solution
Frequency 1 (using wavelength 1) = 6.94927e14 Hz
Frequency 2 (using wavelength 2) = 1.1601e15 Hz
Delta Frequency = 4.65173e14
Energy 1 (using eV1) =8.571644e-20 J
Energy 2 (using eV2) =4.0375e-19 J
Delta Energy = 3.18032e-19
thus, Delta Energy over Delta Frequency gives me my experimental h...
h = 6.83685e-34 Js
That's all fine and good... but
I have NO idea how to solve for the work function.
Greatly appreciate a reply, this is my last question of the day.