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 = 1.26, uniformly covers the top of a glass plate, n = 1.61. 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 green, 543-nm light as it travels through the film?
684 nm
431 nm
337 nm
543 nm
omit
Question 3
At what minimum non-zero thickness of the film will the intensity of the green light reflected back into the air be a maximum?
108 nm
272 nm
136 nm
215 nm
omit
Question 4
At what minimum non-zero thickness of the film will the intensity of the same green light reflected back into the air be a minimum, or experience destructive interference?
215 nm
108 nm
272 nm
136 nm
omit
Question 5
In general, when green light is removed from white light, the film would appear to be which color?
grey
magenta
cyan
yellow
omit
Question 6
What is the frequency of the green light as it travels through the film?
5.52 x 10
14
hz
4.38 x 10
14
hz
1.29 x 10
20
hz
6.96 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?
1.22 x 10
-12
sec
1.81 x 10
-12
sec
8.33 x 10
-10
sec
1.34 x 10
-9
sec
1.53 x 10
-12
sec
PhysicsLAB
Copyright © 1997-2021
Catharine H. Colwell
All rights reserved.
Application Programmer
Mark Acton