Question

A double-slit arrangement produces interference fringes for yellow sodium light. To produce narrower-spaced fringes, should red light or blue light be used?

a. blue lightb. red light

Answer 1

Blue light

Step-by-step explanation:

y=Lwm/d

where:

y is the distance between the finges

w is the wavelength is light (I dont have a symbol for lambda)

m is the fringe order (the central bright fringe is the zeroth- order, the next on either side is the + or - first order, et cet)

d is the distace between the slits

So to reduce y, the spacing between the fringes, you could move your screen closer to the slits, use slits that are spaced farther apart, or use a shorter wavelength of light (shift toward the blue)