A glass plate ( n = 1.53) that is 0.495 m thick and surrounded by air is illumin

ID: 1464394 • Letter: A

Question

A glass plate (n = 1.53) that is 0.495 m thick and surrounded by air is illuminated by a beam of white light normal to the plate.

What wavelengths (in air) within the limits of the visible spectrum ( = 400 nm to 700 nm) are intensified in the reflected beam?

If there is more than one correct answer enter your answers separating them with commas. (in nm)

What wavelengths are cancelled in the reflected light?

If there is more than one correct answer enter your answers separating them with commas. (in nm)

apply for Constructive interference

2nt = (m + 0.5) L

Where m = (0, 1, 2, ...)

t is thickness

n is refractive index

for m = 1,

L = 2 * 1.53 * 0.495 e -6 /1.5

L = 1009.8 nm
--------------------------------------------
for m =2

L2 = 2 * 1.53 * 0.495 e -6 /2.5

lambda = 604.8 nm

--------------------------------
for m = 3

L = 2 * 1.53 * 0.495 e -6 /3.5

L = 432.7 nm
--------------------------

for m = 4

L = 2 * 1.53 * 0.495 e -6 /4.5

L = 336.6 nm

------------------------------------------------

The only visible wavelength in air for which there is destructive interference

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.