Calculating Wavelength of Electron Emission

AI Thread Summary
The discussion centers on calculating the wavelength of light emitted when an electron recombines with a hole, losing 2.6 eV of energy. The initial formula used is correct, but there is a critical need to convert the energy from electron volts (eV) to joules for accurate results. The conversion factor is 1 eV = 1.60217646 x 10^(-19) joules. The calculated wavelength appears incorrect due to this oversight, leading to an unusually high energy photon result. Ensuring proper unit conversion is essential for accurate wavelength calculations.
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I need to make sure my method and the formula I have used is correct. Also, my answer for the wavelength seems slightly dodgy. :rolleyes:

Homework Statement


An electron recombines with a hole losing 2.6eV of electrical potential energy. Calculate the wavelength of the light emitted.

Homework Equations


Not given. Equations have to be used ourself.

The Attempt at a Solution


E = \frac{hc}{\lambda}

\lambda = \frac{hc}{E}

\lambda = \frac{(6.63 \times 10^{-34})(3.00 \times 10^8)}{2.6}

\lambda = 7.65 \times 10^{-26}m
 
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Put units on things and make sure they match up. You'll want to convert 2.6eV to joules.
 
You've found the most high energy photon I've ever heard of! ! ! ! Always check the units, you forgot to convert the energy from eV's to Joules.

and I see now that dick just recommended the same thing. . .
 
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How would I change eV's to Joules?
 
1eV=1.60217646*10^(-19) joules. That's what google says when I type in 'electron volt', anyway.
 
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