Waves Test
Honors Physics
Equation Bank:
name __________________
v = f
n1sin1 = n2sin2
True/False
Choose T (True) or F (False) for each of the following statements.
1.)
2.)
3.)
4.)
5.)
Waves transfer energy.
In order to make a wave, something must vibrate.
Sound waves are transverse waves.
Light is not a wave.
On a standing wave, antinodes are places where the amplitude is zero.
Multiple Choice. Darken the bubble of the best answer.
6.)
A car is sounding its horn as it moves. As it drives by, the sound of the horn changes pitch.
This is due to a concept known as _____.
A.) resonance
B.) the Doppler Effect
C.) destructive interference
D.) constructive interference
In the picture to the right, two waves are moving
toward each other. Eventually they will meet and
overlap between points A and B pictured.
The pulses are of equal but opposite amplitude.
Answer the next two questions based on this.
A
B
7.)
The best description of the result when the waves overlap between points A and B is _____.
A.) an increase in frequency
B.) an increase in amplitude
C.) a large crest
D.) cancellation
8.)
The resulting effect can best be explained as ____.
A.) resonance
B.) the Doppler Effect
C.) destructive interference
D.) constructive interference
9.)
The best example of resonance listed below is : ____.
A.) A child kicks his legs while on a swing to go back and forth higher and higher.
B.) Light passes through a prism and forms a rainbow.
C.) A train passes by some ringing bells and the pitch of the bells seems to change.
D.) Two waves meet and they destructively interfere.
10.)
The pitch of a sound is most closely associated with the ____ of the sound.
A.) crests
B.) troughs
C.) amplitude
D.) frequency
11.)
12.)
According to the picture to the right, Wave I
has the _____ compared to Wave II.
A.) lower frequency and smaller wavelength
B.) lower frequency and bigger wavelength
C.) higher frequency and bigger wavelength
D.) higher frequency and smaller wavelength
Wave I
Wave II
In a sound wave, these regions noted are called ____.
A.) refractions
B.) reflections
C.) rarefactions
D.) crests
?
13.)
If a crest of one light wave meets the trough of another light wave ____.
A.) nothing happens because light is not even a wave
B.) the light wave that they make, together, is even brighter
C.) the waves may cancel to cause darkness
14.)
In order to refract, light must enter a second medium ____
A.) at an angle, only
B.) and change speed, only
C.) at an angle and change speed
D.) that must be water
A
B
15.)
In the picture to the right, the path that the
light would take is ____. Hint: The light is
passing from air into water, from a lower to a higher index.
A.) A
B.) B
C.) C
D.) D
C
C D
D
16.)
Someone erases a mistake at a desk by moving the eraser back and forth over his paper. The
desk at which he is seated begins to move back and forth in stride with the erasing. The desk,
as a result moves with greater and greater side-to-side motion. The erasing, in this example, is
acting as a(n) ____.
A.) natural frequency B.) index of refraction C.) index of rarefaction D.) forced vibration
17.)
In a _____ wave, the direction of wave propagation is perpendicular to the direction of
vibration of the source. These kinds of waves have both ___________________.
A.) transverse; compressions and rarefactions
B.) longitudinal; compressions and rarefactions
C.) transverse; crests and troughs
D.) longitudinal; crests and troughs
18.)
The best sentence that describes refraction is ____.
A.) The bouncing of light or any wave off a surface
B.) The bending of light or any wave as it passes from one medium into another
C.) The areas of a longitudinal wave that are opposite the compressions
D.) The spreading out of a wave as it passes through an opening
19.)
A solid block of wood is struck with a hammer
as shown. Consequently, a region of high density
at passes “P” along the direction indicated.
This region is best described as a _____ and is
part of a _____ wave moving through the wood.
A.) rarefaction; transverse
B.) rarefaction; longitudinal
C.) compression; transverse
D.) compression; longitudinal
P
20.)
The index of refraction of a particular glass is nglass = 1.5. The index for a certain kind of
plastic is nplastic = 1.4. Which of the following is true regarding these media?
A.) the speed of light is faster in the glass than it is the plastic
B.) light can travel about one and a half times faster through the glass than in air
C.) the density of the plastic is greater than that of the glass
D.) none of the above
21.)
When the forced vibration of a tuning fork’s sound waves match the natural frequency of a
column of air, the sound gets louder. This is an example of ____.
A.) resonance
B.) the Doppler Effect
C.) dispersion
D.) refraction
22.)
A coil is shaken so that a standing wave is generated. The positions marked on this standing
wave are called ______.
A.) nodes
B.) antinodes
C.) dispersion
D.) diffraction points
?
23.)
The speed of sound is taken as 340 m/s. What frequency will produce a sound wave that is
0.17 m long?
A.) 5 x 10-4 Hz
B.) 54 Hz
C.) 57.8 Hz
D.) 2000 Hz
A child is standing next to a large pool of water. She can make waves by pushing a ball up and down.
Here is a picture of the first few waves she made. A distance is indicated on the picture, too.
20 feet
24.)
25.)
How many full, up-and-down vibrations did the ball make.
A.) 5
B.) 10
C.) 15
D.) 20
What is the wavelength?
A.) 2 feet
B.) 4 feet
D.) 8 feet
C.) 6 feet
26.)
If the child wanted to make the waves longer, she would move the ball up and down ____.
A.) a bigger distance
B.) a smaller distance
C.) more times per second
D.) fewer times per second
27.)
The kind of waves that she made, this way, are called ____ waves.
A.) transverse
B.) compression
C.) longitudinal
D.) electromagnetic
28.)
To make waves with a smaller amplitude, the ball would have to be moved _____.
A.) a bigger up-and-down distance
B.) a smaller up-and-down distance
C.) more times per second
D.) fewer times per second
29.)
The bouncing of a wave off a surface is ____.
A.) reflection
B.) dispersion
C.) resonance
D.) the Doppler Effect
30.)
In which of these pictures is the reflection of a ray of light off a mirror correctly drawn?
The ray has an angle of incidence of 40o.
40o 40o
40o 45o
40o 50o
A.)
B.)
C.)
40o
60o
D.)
31.)
Straight waves are approaching two small openings. The waves undergo no change in speed
since the medium on both sides of the barrier is the same. After passing through, the waves
appear as pictured. The wave property that is best exhibited is ____.
A.) reflection
B.) interference
C.) refraction
D.) Doppler Effect
Direction of
wave motion
P
32.)
In the drawing, above, a point P is located on the right side of the two openings through which
The waves are passing. What phrase best describes the nature at point P?
A.) Point P is on a nodal line where the waves are undergoing constructive interference
B.) Point P is on an antinodal line where the waves are undergoing constructive interference
C.) Point P is on a nodal line where the waves are undergoing destructive interference
D.) Point P is on an antinodal line where the waves are undergoing destructive interference
33.)
Each of these wave patterns is moving by at different speeds. The frequency at which the
waves pass is the same for all four. Which of these wave patterns, then, is moving by with the
lowest speed?
A.)
B.)
C.)
D.)
34.)
Light travels at 3 x 108 m/s (300,000,000 m/s). A particular electromagnetic wave moving at
this speed has a wavelength of 5 x 10-3 m (0.005 m). The frequency used to produce this light
is ____.
A.) 60 Hz
B.) 1.67 x 105 Hz
C.) 6 x 105 Hz
D.) 6 x 1010 Hz
35.)
A stationary device sends radio waves with a frequency of 500 Hz. If a stationary observer
detects these waves, the perceived frequency is also 500 Hz. However, if the observer moves
away from the device making these waves, then the perceived frequency for the observer will
be _____.
A.) less than 500 Hz
B.) 500 Hz
C.) greater than 500 Hz
36.)
The period of a 500 Hz wave is _____.
A.) 0.002 s
B.) 0.005 s
C.) 0.05 s
D.) 500 s
A small bug rests on the surface of a small pool of water.
It wiggles its legs with a constant frequency of 3 Hz .
As a result, it sends out a pattern of concentric ripples
(waves) as shown in the diagram on the right.
Points L and R are stationary points relative to the water
located to the left and to the right of the bug.
While continuing to wiggle its legs with a constant frequency of 3 Hz, the bug moves toward
point R. Now answer the following two questions based on this scenario.
37.)
Which of these four wave patterns best shows the possible set of waves generated by the bug as
he moves toward R?
38.)
The frequency at which the waves arrive at point R is _____ 3 Hz.
A.) greater than
B.) equal to
C.) less than
The index of refraction of various substances for a particular wavelength and temperature are
listed here:
Substance
air
water
glass
diamond
Index of refraction (n)
1.00
1.33
1.50
2.42
39.)
Light is shined from water into air. The angle of incidence of the light in the water is 35o. The
angle of refraction for the light in air is most nearly ____ degrees.
a. 26
b. 50
c. 70
d. 76
40.)
Light is incident on a water to glass interface. The light, beginning in the water, makes a 50o
angle of incidence. What is the angle of refraction inside the glass?
a. 33 o
b. 37 o
c. 43 o
d. 53 o
41.)
Light passes from diamond into some unknown substance thus making an angle of refraction of
40o inside the unknown substance. The angle of incidence, inside the diamond is 15o. The
unknown substance, among those listed, is most likely ____.
a. air
b. water
c. glass
d. diamond
42.) What is the expected angle of refraction
if light passes from air into diamond
at an angle of 60 degrees to the normal, as shown?
a. 16 o
b. 21 o
c. 25 o
d. not given
43.)
If light passed from air into any of these media, which would bend light the most?
a. air
b. water
c. glass
d. diamond
EXPERIMENT DESCRIPTION and QUESTIONS
An experimenter sets up an apparatus in which a weight is attached to the end of a 2.0 meter
metal wire. The other end of the wire is guided over a pulley and tied to a small machine that shakes
the end of the wire up and down. Here is a picture of the apparatus with the machine turned “off”
(figure 1).
2m
weight
t
(figure 1)
The weight, the wire’s thickness, and the rate at which the wire is shaken (called vibration
frequency) may all be changed. Some combinations of weight, wire thickness, and vibration frequency
result in stable patterns in the vibrating wire. These are called standing wave segments. Below is a
picture of the apparatus with the machine turned “on” in which a stable wave pattern had been
established (figure 2).
Wave segment
weight
t
(figure 2)
The length of a wave segment (measured in meters, m) can also change when the experimenter
varies the weight (in Newtons, N), wire thickness (in millimeters, mm), or vibration frequency (in
Hertz, Hz). A picture of the laboratory apparatus with a change in conditions resulting in a new length
of wave segment is shown in this diagram (figure 3)
Wave segment
(figure 3)
weight
t
In each of the following experiments, the investigator performed a simple procedure as
described then recorded and tabulated the following data.
EXPERIMENT 1
The investigator set the vibration frequency to 50 Hz. The wire’s thickness was 1.0 mm and
presumed to be constant. Throughout the experiment, the experimenter changed the weight. When the
string showed a stable pattern, the weight and the corresponding length of a wave segment were
recorded. The results are tabulated in TABLE 1.
TABLE 1
Weight
(N)
100.0
25.0
11.1
6.25
4.00
Length of Wave
Segment (m)
2.00
1.00
0.66
0.50
0.40
EXPERIMENT 2
In this investigation, the experimenter used the same 1.0 mm thick wire but used a 25 N weight
for each trial. He changed the machine’s vibration frequency gradually until a stable wave pattern
resulted. Then, he would record this frequency and its corresponding length of a wave segment in
TABLE 2.
TABLE 2
Vibration
Frequency
(Hz)
25
50
75
100
125
Length of Wave
Segment (m)
2.00
1.00
0.66
0.50
0.40
Now answer the following questions based on the above.
44.)
Before performing Experiment 2, the investigator wrote a hypothesis. Which of the following
hypotheses is the most appropriate for Experiment 2?
A.) As the length of a wave segment is made larger, its corresponding frequency will increase.
B.) If 25 Newtons is used for a weight, there should be a change in the length of the wave
segment and the frequency.
C.) As the wire thickness is increased, the vibration frequency is increased by 25 Hz.
D.) If the vibration frequency is increased, then the length of a wave segment will decrease.
E.) The vibration frequency must change in order to make a stable wave pattern for a particular
weight and wire thickness.
45.)
Suppose the experimenter used a vibration frequency of 150 Hz on the 1.0 mm wire weighted
with 25 N as in Experiment 2. The length of the resulting wave segment would most likely be
____.
A.) 0.33 m
B.) 0.44 m
C.) 1.44 m
D.) 2.44 m
E.) 3.44 m
46.)
Suppose the experimenter used a 1.0 mm string weighted with 6.25 N. What would be the
length of the resulting wave segment if a vibration frequency of 100 Hz was used?
A.) 0.25 m
B.) 0.50 m
C.) 0.75 m
D.) 1.00 m
E.) 1.25 m
47.)
While performing Experiment 1, the investigator did not record a trial in which a weight
between 25 N and 100 N was used. The best reason for not using weights from 25 – 100 N is
that ____.
A.) these weights would have been too much for the wire to hold
B.) these weights may have stretched the wire very much
C.) the wave segments formed using these weights were too small
D.) the wave segments formed using these weights were too large
E.) no stable wave patterns were formed for these weights
48.)
Among the following graph, which one depicts the relationship between the weight on the wire
and the length of a wave segment as explored by Experiment 1?
(For these graphs, assume that the weight on the wire is on the horizontal axis while the length
of a wave segment is on the vertical axis.)
None of these
A.)
B.)
C.)
D.)
E.)
49.)
Suppose a third Experiment was performed in which a 25 N weight was used for all trials.
Furthermore, the vibration frequency was kept the same, as well, at 50 Hz. However, in this
investigation, wires of various thickness were used.
Which of the following is an appropriate goal for this new experiment:
A.) To determine the effects of frequency on wire thickness
B.) To determine the effects of wire thickness on frequency
C.) To determine just how much weight wires of various thicknesses could hold
D.) To determine the effects of changing frequency on length of a wave segment
E.) To determine the effects of changing wire thickness on length of a wave segment
50.)
In the graph to the right, Experiment 2
was repeated for a different string.
Using the graph, find the best
estimation of the length of a wave
segment when the vibration frequency
was 75 Hz.
A.) 1.00 m B.) 0.50 m C.) 0.33 m
D.) 0.25 m E.) 0.20 m
Length of wave segment vs Frequency
1.50
Length
of wave 1.00
segment
(m)
0.50
0
0
50
100
Frequency (Hz)
150