Interference and Diffraction
Practice Test
1.
What did Roemer prove?
a.
light travels at a finite speed
b.
the correct speed of light
c.
light has no speed
d.
light travels instantaneously
Hint
2.
A wave that reflects off a flat surface will reflect at __________.
a.
a different angle from which it struck the surface
b.
a right angle to the surface
c.
an angle of zero
d.
the same angle at which it struck the surface
Hint
3.
__________ is the point of the largest displacement where two waves meet.
a.
A period
b.
An antinode
c.
A crest
d.
A node
Hint
4.
Why are larger telescope lenses important?
a.
They have reduced resolving power to make objects clearer.
b.
They reflect less light back into space.
c.
They have greater resolving power.
d.
They focus the same amount of light as a smaller lens, but they are sharper.
Hint
5.
Why are bigger lenses better for observing dim objects?
a.
they collect more light
b.
they refract light less
c.
they have better curvatures
d.
they reduce spherical aberration
Hint
6.
Your image in a bathroom mirror results from __________.
a.
specular reflection
b.
diffuse refraction
c.
diffuse reflection
d.
specular refraction
Hint
7.
Monochromatic light passing through a single slit will produce a diffraction pattern __________ a double slit.
a.
twice as wide as
b.
different from
c.
the same as
d.
clearer than
Hint
8.
In nearsightedness, the image is focused __________.
a.
in front of the retina
b.
in front of the eye
c.
beyond the retina
d.
directly on the retina
Hint
9.
When you wear polarized sunglasses, the Sun's light intensity to your eyes is __________.
a.
cut in half
b.
doubled
c.
completely eliminated
d.
reduced by 1/4
Hint
10.
Farsightedness can be corrected with a __________.
a.
convex lens
b.
plane lens
c.
concave lens
d.
parabolic lens
Hint
11.
Danish astronomer Ole Roemer first measured the speed of light by studying __________.
a.
the Moon
b.
how lasers travel in space
c.
how light traveled around two mountains
d.
the orbit of Io, a moon of Jupiter
Hint
12.
Bright bands in interference fringes result from __________.
a.
destructive interference
b.
destructive diffraction
c.
constructive interference
d.
constructive diffraction
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.
0.75 m
b.
0.80 m
c.
1.33 m
d.
1.25 m
Hint
14.
In a ray tracing diagram, two rays must pass through the __________ to determine the location of the image.
a.
image
b.
lens edge
c.
focal point
d.
object
Hint
15.
Blue light, which is bent more than red light in a prism, has __________.
a.
a longer wavelength
b.
a lower frequency
c.
a shorter wavelength
d.
a faster speed
Hint
16.
A light ray is traveling through an unknown material when it intersects ethanol (
n
= 1.36) at an incident angle of 62.0°. If the angle of refraction is 46.4°, what is the index of refraction of the unknown material?
a.
1.12
b.
1.66
c.
2.00
d.
0.985
Hint
17.
Why did Young place a single slit between the light source and the double slit?
a.
to filter out other colors of light
b.
A single source of light is needed.
c.
Light needs to escape the system.
d.
to make the light waves coherent
Hint
18.
A light ray traveling through crown glass (
n
= 1.52) intersects a sheet of flint glass (
n
= 1.61) at an angle of 27.3°. What is the angle of refraction?
a.
33.0°
b.
25.7°
c.
0.839°
d.
0.433°
Hint
19.
The focal length of a concave lens is __________.
a.
positive
b.
negative
c.
magnified
d.
reduced
Hint
20.
How does light normally travel?
a.
in concentric circles
b.
always toward a dark area
c.
in a straight line
d.
in a curved line
Hint
