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### Calculating Wavelength of electron

Posted: Sun Nov 04, 2018 12:54 am
If the wavelength of incident light on sodium metal was 810 nm, and the work function of
sodium is 1.1 eV, what is the wavelength of the ejected electron?

Am I correct in using de Broglie's equation because the wavelength we are trying to calculate is a particle not a photon?

I got 1.86*10^-9 m.

pls help

### Re: Calculating Wavelength of electron

Posted: Sun Nov 04, 2018 12:56 am
I haven’t done the computation for this lol but you’re right to use deBroglie, as the question isn’t for a photon

### Re: Calculating Wavelength of electron

Posted: Sun Nov 04, 2018 4:33 pm
Do you use de Broglie when calculating wave length for an electron and c=lambda times frequency for a photon?

### Re: Calculating Wavelength of electron

Posted: Sun Nov 04, 2018 4:57 pm
The equation you would use is Energy (photon) - Work Function=Kinetic Energy of Electron=1/2mv^2. And then use the known value of mass of electron to solve for velocity to plug into heisenberg's.