Archived Quantum Mechanics Question - Work function and h

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The discussion focuses on calculating Planck's constant and the work function of aluminum using photoelectron energy data. The maximum energy of photoelectrons is provided for two different wavelengths, allowing for the formulation of two equations. The equations relate the energy of the photons to the work function and the kinetic energy of the emitted electrons. The approach involves solving these equations simultaneously to eliminate one variable and find the values of Planck's constant and the work function. The method outlined is correct, confirming the relationship between photon energy, work function, and kinetic energy.
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Quantum Mechanics Question -- Work function and h

The maximum energy of photoelectrons from aluminum is 2.3 eV for radiation of 200 nm and 0.90 eV for radiation of 259 nm. Use these data to calculate Planck's constant and the work function of aluminum.

Do I have it right?:

E_{electron} = E_{photon} + W

(1) : 2.3 eV = \frac{hc}{200 nm} + W

(2) : 0.90 eV = \frac{hc}{258 nm} + W

Two equations with two unknonws (h and W), so I just solve, right? Seems pretty simple, I'm just not sure if I'm using the right equations.
 
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Some energy of the photon is used to "knock" the electron (work function) and the rest is given to electron as kinetic energy. So
Ephoton = W + KEelectron, so KEelectron = Ephoton - W. Now, having corrected this, we can subtract (1) and (2) part by part, so eliminate W and find h. Then we trivially find W.
 
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