Monochromatic light is incident on a grating that is 75 mm wide and ruled with 50,000 lines. The second-order maximum is seen at 32.5°. What is the wavelength of the incident light? 202 nm 605 nm 806 nm 403 nm 452 nm
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Answer:
= 403 nm
Explanation:
We have the condition for the maximum for a diffraction grating
d sinθ =mλ
Then the grating constant d = w/N
= (75 mm)/(50,000)
= 0.0015 mm
Then wavelength of light is λ = (dsinθ)/m
= (0.0015 mm)(sin 32.5)/2
=403*10-6 mm
= 403 nm