Practice Problems
Thin Film Interference Glass Coating
Directions:
On this worksheet you will be investigating the basic properties of
thin film interference
revealed in different thicknesses film on glass.
omit
Question 1
A thin film, n = 1.27, uniformly covers the top of a glass plate, n = 1.6. 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 red, 738-nm light as it travels through the film?
937 nm
461 nm
738 nm
581 nm
omit
Question 3
At what minimum non-zero thickness of the film will the intensity of the red light reflected back into the air be a maximum?
291 nm
369 nm
145 nm
185 nm
omit
Question 4
At what minimum non-zero thickness of the film will the intensity of the same red light reflected back into the air be a minimum, or experience destructive interference?
291 nm
185 nm
369 nm
145 nm
omit
Question 5
In general, when red light is removed from white light, the film would appear to be which color?
yellow
grey
cyan
magneta
omit
Question 6
What is the frequency of the red light as it travels through the film?
3.2 x 10
14
hz
4.07 x 10
14
hz
1.74 x 10
20
hz
5.16 x 10
-4
hz
omit
Question 7
If the glass plate is 25 centimeters thick, how many seconds would be required for the transmitted beam to travel through the glass?
8.33 x 10
-10
sec
1.45 x 10
-12
sec
1.13 x 10
-12
sec
1.74 x 10
-12
sec
1.33 x 10
-9
sec
PhysicsLAB
Copyright © 1997-2021
Catharine H. Colwell
All rights reserved.
Application Programmer
Mark Acton