# Michelson interferometer

1. Feb 19, 2007

### pari786

1. The problem statement, all variables and given/known data

A Michelson interferometer uses light from a sodium lamp. Sodium atoms emit light having wavelengths 589.0 nm and 589.6 nm. The interferometer is intially set up with both arms of equal length (L1=L2) producing a bright spot at the center of the interference pattern. How far must mirror M2 be moved so that one wavelength has produced one more new maxima than the other wavelength?

2. Relevant equations

wavelength = 2 (delta L) / (delta m)

3. The attempt at a solution

I know that we are looking for delta L but I don't know which wavelength and m value to use.

2. Feb 19, 2007

### pari786

I got it how to do it :

let one of the m value be m and the other m+1...both have same L...so sub L value from one equation to the other and then solve for m..once u have m, sub in one of the equation and find L...

:zzz:

3. Feb 19, 2007

### pari786

I got it how to do it :

let one of the m value be m and the other m+1...both have same L...so sub L value from one equation to the other and then solve for m..once u have m, sub in one of the equation and find L...

but which wavelength to use.