Interference and Diffraction
Practice Test
1.
Thin film constructive interference occurs when the wavelength of a wave is in multiples of __________.
a.
2×wavelength
b.
4×wavelength
c.
1/4 wavelength
d.
1/2 wavelength
Hint
2.
In Figure 16-6, if the candle were moved so that it was 2
d
to the right of the screen, but the lamp was not moved, how would the luminous intensity of the lamp have to be adjusted to make each side of the screen equally illuminated?
a.
It would need to be halved.
b.
It would need to be quadrupled.
c.
It would need to be quartered.
d.
It would need to be doubled.
Hint
3.
Real images produced by mirrors have __________ magnification.
a.
positive
b.
massive
c.
negative
d.
opposite
Hint
4.
According to Snell's law, light traveling from a vacuum to glass will __________.
a.
stop completely
b.
travel at the same speed
c.
slow down
d.
speed up
Hint
5.
If a refracted ray moves away from the normal, the speed of light of the ray in this material is __________ that of the incident ray.
a.
greater than
b.
unrelated to
c.
less than
d.
the same as
Hint
6.
In a double slit experiment with slits 1.0×10
-5
m apart, light casts the first bright band 3.0×10
-2
m from the center of a screen 0.65 m away. What is the wavelength of this light?
a.
430 nm
b.
390 nm
c.
510 nm
d.
460 nm
Hint
7.
__________ is the point of the largest displacement where two waves meet.
a.
A node
b.
A crest
c.
An antinode
d.
A period
Hint
8.
The two main factors affecting the illuminance of an object are __________.
a.
distance and hardness
b.
hardness and color
c.
distance and brightness
d.
color and brightness
Hint
9.
If in Figure 17-4 the image of the lamp is 5 ft behind the mirror and the girl is 1 ft in front of the mirror, where is the lamp?
a.
4 ft behind the girl
b.
10 ft behind the girl
c.
5 ft behind the girl
d.
6 ft behind the girl
Hint
10.
The line perpendicular to the reflective surface is the __________.
a.
normal
b.
line of reflection
c.
line of refraction
d.
line of incidence
Hint
11.
What causes a diffraction grating to produce interference patterns?
a.
Ripples on the surface.
b.
Tiny scratches that act like slits.
c.
A thin film of oil.
d.
Differing thickness of the lens.
Hint
12.
In Figure 18-11, if the top half of the lens is covered, what will happen to the image?
a.
The top half of the image will disappear.
b.
The bottom half of the image will disappear
c.
Nothing.
d.
The image will become dimmer.
Hint
13.
In Figure 17-14, if the object is 4 times farther from the mirror than the image, what is the focal length of the mirror?
a.
1.33 m
b.
1.25 m
c.
0.75 m
d.
0.80 m
Hint
14.
Farsightedness can be corrected with a __________.
a.
parabolic lens
b.
plane lens
c.
concave lens
d.
convex lens
Hint
15.
When a continuous wave meets a boundary that transmits the wave at a lower speed, the wavelength __________.
a.
decreases
b.
interferes with itself
c.
increases
d.
becomes negative
Hint
16.
A hologram is produced as a result of ___________.
a.
reflection
b.
interference
c.
diffraction
d.
refraction
Hint
17.
A polarizer and analyzer will block all light if they are at __________ to each other.
a.
right angles
b.
parallel angles
c.
30° angles
d.
180° angles
Hint
18.
In nearsightedness, the image is focused __________.
a.
in front of the retina
b.
directly on the retina
c.
beyond the retina
d.
in front of the eye
Hint
19.
A concave lens is also known as a __________ lens.
a.
diverging
b.
converging
c.
plane
d.
concave
Hint
20.
Red and blue light make __________.
a.
purple
b.
indigo
c.
magenta
d.
violet
Hint
