Consider two diffraction gratings; one has 4000 lines per cm and the other one has 6000 lines per cm.
A) Both gratings produce the same dispersion, but the orders are sharper for the 6000-line grating.
B) The 4000-line grating produces the greater dispersion.
C) Both gratings produce the same dispersion, but the orders are sharper for the 4000-line grating.
D) The 6000-line grating produces the greater dispersion.

Question

Quizplus · Accepted Answer

The dispersion of a diffraction grating increases with the number of lines per unit length. Therefore, the 6000-line grating, having more lines per cm, produces greater dispersion than the 4000-line grating.

Consider Two Diffraction Gratings; One Has 4000 Lines Per Cm