Diffraction Grating If you have light with a wavelength of 6

Diffraction Grating: If you have light with a wavelength of 630 nm and a grating with 6000 lines/cm what is the angle at which the first order diffracted beam will be seen?

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Solution

Wave length =630 * 10 ^ -9 m

No.of slits in 1 cm is = 4400

No.of slits in 1 m is N = 600000

Grating element d = 1/ N

= 0.00000166 m

Condition for 1 st maximum d sin =

from this sin = / d

= 630*10^-9)/(0.00000166) = 0.3795

= 22.30 degrees