# Wavelength, Electron

1. Mar 7, 2008

### Air

I need to make sure my method and the formula I have used is correct. Also, my answer for the wavelength seems slightly dodgy. :uhh:

1. The problem statement, all variables and given/known data
An electron recombines with a hole losing 2.6eV of electrical potential energy. Calculate the wavelength of the light emitted.

2. Relevant equations
Not given. Equations have to be used ourself.

3. The attempt at a solution
$E = \frac{hc}{\lambda}$

$\lambda = \frac{hc}{E}$

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

$\lambda = 7.65 \times 10^{-26}m$

2. Mar 7, 2008

### Dick

Put units on things and make sure they match up. You'll want to convert 2.6eV to joules.

3. Mar 7, 2008

### AstroRoyale

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. . .

Last edited: Mar 7, 2008
4. Mar 7, 2008

### Air

How would I change eV's to Joules?

5. Mar 7, 2008

### Dick

1eV=1.60217646*10^(-19) joules. That's what google says when I type in 'electron volt', anyway.