# How do you calculate the wavelength of a helium-neon laser that says 95mW on it?

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I have already done a diffraction grating but would like to double check that my results are accurate. I thought that calculating the wavelength of the laser I had used would give me more marks. Is it even possible to calculate the wavelength like this?

Thanks

I have already done a diffraction grating but would like to double check that my results are accurate. I thought that calculating the wavelength of the laser I had used would give me more marks. Is it even possible to calculate the wavelength like this?

Thanks

##### 1 Answer

Aug 16, 2017

#### Explanation:

632.8 nm is the normally quoted wavelength, giving a frequency of 4.74 x

The best way to measure the wavelength and hence find the frequency is by measuring diffraction patterns as you did. Most students can get within 1 or 2% with reasonable technique.