A monochromatic beam of light of wavelength 600 nm falls on a grating at normal incidence and produces a second-order image at an angle of 30º.The grating spacing must be
A)0.60 µm
B)2.4 µm
C)0.30 µm
D)1.4 µm
E)1.0 µm

Question

Quizplus · Accepted Answer

The grating equation is d*sin(θ) = m*λ, where d is the grating spacing, θ is the angle, m is the order, and λ is the wavelength. For m=2, λ=600 nm, and θ=30º, solving gives d = 2.4 µm.

A Monochromatic Beam of Light of Wavelength 600 Nm Falls