Practice Problems
Thin Film Interference Glass Coating
Directions:
On this worksheet you will be investigating the basic properties of
thin film interference
.
omit
Question 1
A thin film, n = 1.39, uniformly covers the top of a glass plate, n = 1.55. If the medium above the film is air, at which of the interfaces (air-film and film-glass) does the light undergo a 180° phase change upon reflection?
at both interfaces
at neither interface
air-film
film-glass
omit
Question 2
What is the wavelength of blue, 459-nm light as it travels through the film?
638 nm
459 nm
330 nm
296 nm
omit
Question 3
At what minimum non-zero thickness of the film will the intensity of the blue light reflected back into the air be a maximum?
83 nm
230 nm
115 nm
165 nm
omit
Question 4
At what minimum non-zero thickness of the film will the intensity of the same blue light reflected back into the air be a minimum, or experience destructive interference?
165 nm
230 nm
115 nm
83 nm
omit
Question 5
In general, when blue light is removed from white light, the film would appear to be which color?
magneta
yellow
cyan
grey
omit
Question 6
What is the frequency of the blue light as it travels through the film?
9.08 x 10
-4
hz
6.54 x 10
14
hz
4.7 x 10
14
hz
9.91 x 10
19
hz
omit
Question 7
If the glass plate is 28 centimeters thick, how many seconds would be required for the transmitted beam to travel through the glass?
2.03 x 10
-12
sec
9.33 x 10
-10
sec
1.76 x 10
-12
sec
1.48 x 10
-12
sec
1.45 x 10
-9
sec
PhysicsLAB
Copyright © 1997-2018
Catharine H. Colwell
All rights reserved.
Application Programmer
Mark Acton