Question

A student shines a monochromatic light through a diffraction rating and observes the resulting interference pattern on a screen. If the student wishes to increase the distance between the first order fringe and the central maxima, the student should
A. use a light with a larger wavelength

B. move the diffraction grating closer to the screen

C. increase the distance between the slits in the diffraction grating

D. more than one of the above options will work

Answer 1

Answer:

(C) increase the distance between the slits in the diffraction grating

Explanation:

This light always form constructive interference, the difference in distance is given λn.

where;

λ is the wavelength

n is the nth maxima

At center fringe, n = 0; the difference is 0

for the first maximum, n= 1, the difference is λ

for second maximum, n = 2, the difference is 2λ

for third maximum, n = 3, the difference is 3λ

From the above illustrations, the wavelength is constant, but the distances between the slits increases, resulting in a higher difference.

Therefore, Option C is the correct answer: increase the distance between the slits in the diffraction grating