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Name: 
 

ch 24


Multiple Choice
Identify the letter of the choice that best completes the statement or answers the question.
 

 1. 
Interference effects observed in the early 1800's were instrumental in supporting a concept of the existence of which property of light?
a.
polarization
b.
particle nature
c.
wave nature
d.
electromagnetic character
e.
finite speed of propagation
 

 2. 
If a wave from one slit of a Young's double-slit set-up arrives at a point on the screen one wavelength behind the wave from the other slit, what is observed at that point?
a.
dark fringe
b.
bright fringe
c.
multi-colored fringe
d.
gray fringe, neither dark nor bright
 

 3. 
A Young's double slit has a slit separation of 2.50 ´ 10-5 m on which a monochromatic light beam is directed. The resultant bright fringes on a screen 1.00 m from the double slit are separated by 2.30 ´ 10-2 m. What is the wavelength of this beam? (1 nm = 10-9 m)
a.
373 nm
b.
454 nm
c.
575 nm
d.
667 nm
e.
759 nm
 

 4. 
In order to produce a sustained interference pattern by light waves from multiple sources, which of the following conditions must be met?
a.
sources are coherent
b.
sources are monochromatic
c.
Both choices above are valid.
d.
None of the choices above are valid.
 

 5. 
In a Young's double-slit interference apparatus, by what factor is the distance between adjacent light and dark fringes changed when the separation between slits is doubled?
a.
1/4
b.
1/2
c.
1
d.
2
e.
4
 

 6. 
A Young's double-slit apparatus is set up where a screen is positioned 0.80 m from the double slits. If the distance between alternating bright fringes is 0.95 cm and the light source has a wavelength of 580 nm, what is the separation of the double slits? (1 nm = 10-9 m)
a.
2.8 ´ 10-5 m
b.
4.9 ´ 10-5 m
c.
5.6 ´ 10-5 m
d.
6.0 ´ 10-5 m
e.
7.4 ´ 10-5 m
 

 7. 
Two beams of coherent light are shining on the same piece of white paper. With respect to the crests and troughs of such waves, darkness will occur on the paper where:
a.
the crest from one wave overlaps with the crest from the other.
b.
the crest from one wave overlaps with the trough from the other.
c.
the troughs from both waves overlap.
d.
darkness cannot occur as the two waves are coherent.
e.
darkness occurs anyway.
 

 8. 
After light from a source passes through two slits, a first order bright spot is seen on the wall at point P. Which distance is equal to the wavelength of the light?

pretest_ch-_24_files/i0090000.jpg
a.
the extra distance one beam must travel
b.
the distance between beams as they leave the slit
c.
the distance of point P from the central point of the interference pattern
d.
the distance between slits
e.
one-half of the distance between slits
 

 9. 
That light can undergo interference is evidence that it:
a.
has electric properties.
b.
is made of corpuscles.
c.
behaves like a wave.
d.
has a phase of 180º.
e.
behaves like a transversal wave.
 

 10. 
In a Young's experiment, the paths from the slits to a point on the screen differ in length causing destructive interference at the point. Which of the following path difference would cause this destructive interference?
a.
5l/2
b.
3l/4
c.
4l
d.
7l/4
e.
none of the above
 

 11. 
The blue tint of a coated camera lens is largely caused by what effects?
a.
diffraction
b.
refraction
c.
polarization
d.
interference
e.
absorption
 

 12. 
A silicon monoxide thin film (n = 1.45) of thickness 90.0 nm is applied to a camera lens made of glass (n = 1.55). This will result in a destructive interference for reflected light of what wavelength?
a.
720 nm
b.
558 nm
c.
522 nm
d.
450 nm
e.
376 nm
 

 13. 
When light shines on a lens placed on a flat piece of glass, interference occurs which causes circular fringes called Newton's rings. The two beams that are interfering come:
a.
from the top and bottom surface of the lens.
b.
from the top surface of the lens and the top surface of the piece of glass.
c.
from the bottom surface of the lens and the top surface of the piece of glass.
d.
from the top and bottom surface of the flat piece of glass.
e.
from the top surface of the lens and the bottom surface of the piece of glass.
 

 14. 
When light passes from a material with a high index of refraction into material with a low index of refraction:
a.
none of the light is reflected.
b.
some light is reflected without a change of phase.
c.
some light is reflected with a 180º change of phase.
d.
the light that is not reflected has a 180º change of phase.
e.
all the light has a 180º change of phase.
 

 15. 
Upon reflection, light undergoes a 180º phase change:
a.
always.
b.
if the incident medium has the higher index of refraction.
c.
if the incident medium has the lower index of refraction.
d.
whenever the incident angle is less than the critical angle.
e.
whenever the incident angle is more than the critical angle.
 

 16. 
A Fraunhofer diffraction pattern is created by monochromatic light shining through which of the following?
a.
single slit
b.
double slit
c.
triple slit
d.
more than 3 slits
e.
any number of slits
 

 17. 
Light of wavelength 610 nm is incident on a slit of width 0.20 mm and a diffraction pattern is produced on a screen that is 1.5 m from the slit. What is the distance of the second dark fringe from the center of the bright fringe? (1 nm = 10-9 m)
a.
0.68 cm
b.
0.92 cm
c.
1.2 cm
d.
1.4 cm
e.
1.7 cm
 

 18. 
A material is optically active if it:
a.
absorbs light passing through it.
b.
transmits all light passing through it.
c.
exhibits interference.
d.
rotates the plane of polarization of the light passing through it.
e.
changes the wavelength of the light passing through it.
 

 19. 
Unpolarized light is passed through polarizer 1. The light then goes though polarizer 2 with its plane of polarization at 45.0º to that of polarizer 1. Polarizer 3 is placed after polarizer 2. Polarizer 3 has its plane of polarization at 45º to the plane of polarization of polarizer 2 and at 90º to that of polarizer 1. What fraction of the intensity of the original light gets through the last polarizer?
a.
0.707
b.
0.500
c.
0.250
d.
0.125
e.
0.100
 

 20. 
LCD stands for:
a.
linearly collimated diffraction.
b.
longitudinally combined depolarization.
c.
liquid crystal display.
d.
lighted compact disk.
e.
lowest common denominator
 



 
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