Photons and the Photoelectric effect

AI Thread Summary
The discussion revolves around calculating the wavelength of light incident on metallic sodium, given its work function of 2.3 eV and the maximum speed of emitted photoelectrons at 1.08 x 10^6 m/s. Participants clarify that the total energy of the photon is the sum of the work function and the kinetic energy of the emitted electron, which can be calculated using the formula 0.5mv^2. The relationship between photon energy and frequency, along with the connection between frequency and wavelength, is emphasized as crucial for solving the problem. The original poster realizes the solution is simpler than initially thought after receiving guidance. The conversation highlights the importance of understanding energy relationships in the photoelectric effect.
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Homework Statement



Light is incident on the surface of metallic sodium, whose work function is 2.3 eV. The maximum speed of the photoelectrons emitted by the surface is 1.08 106 m/s. What is the wavelength of the light?



Homework Equations



e=hf

p=h/wavelength


The Attempt at a Solution



None so far
 
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What is the kinetic energy imparted to the electron and thus what was the total energy of the photon.
 
Could you be a bit more specific?
 
Well you know the photon energy is the energy needed to remove the electron plus the kinetic energy of the emited electron. You are given the work function (i.e. the energy required to remove the electron) and the electron speed from which you can work out the kinetic energy of the electron. You have already stated the relation between photon energy and frequency. What is the relationship between frequency and wavelength of light?
 
So I use .5mv^2 to get the KE.
From there I divide the sum of the KE and work function by Planck's Constant. I then divide c by f to get the wavelength?
 
Ok, I got it. I made the problem more difficult than it needed to be. Thank you for the help.
 

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