Author Topic: Physics diffraction gratings  (Read 735 times)

Offline tmisterr

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Physics diffraction gratings
« on: February 27, 2010, 10:03:54 am »
If you a question like the 3rd order of light incident normal to a diffration grating happens a theta=45 degreed, find the highest number order possible, how do u approach it?

Offline astarmathsandphysics

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Re: Physics diffraction gratings
« Reply #1 on: February 27, 2010, 10:25:12 am »
sin theta =nw/d where w=wavelength
sin 45= 3w/d
1/3sqrt(2)=w/d
1>nw/d=n*1/3sqrt(2)
n<3sqrt(2)=4.2....
highest order =4

Offline tmisterr

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Re: Physics diffraction gratings
« Reply #2 on: February 28, 2010, 03:22:23 pm »
thanks alt :)