Diffraction grating: A diffraction grating has 300 lines per mm. If light of wavelength 630 nm is sent through this grating, what is the highest order maximum that will appear?
A) 8
B) 2
C) 6
D) 5
E) 5.3

Question

Quizplus · Accepted Answer

The formula to find the highest order maximum is mλ = d(sinθ). Here, m is the order maximum, λ is the wavelength of light, d is the distance between adjacent grooves on the grating, and θ is the angle between the incident light and the direction of the maximum. Solving for m, we get m = (dsinθ)/λ. The highest order maximum occurs when sinθ = 1, which gives m = d/λ. Substituting the given values, we get m = (1/300)/630x10^-9 = 5. So the highest order maximum that will appear is 5.

Diffraction Grating: a Diffraction Grating Has 300 Lines Per Mm