A grating with 396 lines/mm is illuminated with light of wavelength 343 nm.What is the angular separation between the two second-order bright fringes?

Question

Quizplus · Accepted Answer

The angular separation between the two second-order bright fringes is given by:$$	heta = \sin^{-1}\left(\frac{m\lambda}{d}ight)$$where:* m is the order of the bright fringe (m = 2)* λ is the wavelength of light (λ = 343 nm)* d is the grating spacing (d = 1/396 mm)Plugging in these values, we get:$$	heta = \sin^{-1}\left(\frac{2 	imes 343 	imes 10^{-9} 	ext{ m}}{1/396 	imes 10^{-3} 	ext{ m}}ight) = 31.5^\circ$$Therefore, the correct answer is A.

A Grating with 396 Lines/mm Is Illuminated with Light of Wavelength