CHAPTER 10
If the frequency of a certain wave is 10 Hz, its period is
0.1 s
A mass on the end of a spring bobs up and down 1 complete cycle every 2 s. Its frequency is
0.5 Hz
A weight suspended from a spring bobs up and down one complete cycle every 2 s. Its frequency is
0.5 Hz
A 340-Hz sound wave travels at 340 m/s in air with a wavelength of
1 m
The frequency of the second hand on a clock is
1/60 Hz
A wave having a frequency of 1000 Hz vibrates at
100 cycles per second
How many vibrations per second are associated with a 101-MHz radio wave?
101,000,000
Suppose you sound a 1056-Hz tuning fork when you strike a note on the piano and hear 2 beats/second. You tighten the piano string very slightly and now hear 3 beats/second. What is the frequency of the piano string?
1059 Hz
A floating leaf oscillates up and down two complete cycles each 1 s as a water wave passes by. What is the wave's frequency?
2 Hz
As a train of water waves goes by, a piece of cork floating on the water bobs up and down one complete cycle each second. The waves are 2 m long. What is the speed of the wave?
2 m/s
A weight suspended from a spring bobs up and down one complete cycle every 2 s. Its period is
2 s
The range of human hearing is about
20 Hz- 20,000 Hz
A floating leaf oscillates up and down 2 complete cycles in 1 s as a water wave of wavelength 10 m passes by. What is the wave's speed?
20 m/s
Resonance occurs when a 200-Hz tuning fork encounters a sound wave with a frequency of
200 Hz
Ultrasonic sound that travels at 1530 m/s in ocean water is bounced off the ocean floor and returns to the ship above. If the round trip takes 3 s, the depth of the water is
2295 m
A general rule for estimating the distance in kilometers between an observer and a lightning bolt is to count the number of seconds between seeing the lightning and hearing it, and dividing by
3
A wave oscillates up and down two complete cycles each 1 s. If the wave travels an average distance of 6 m in 1 s, its wavelength is
3 m
A skipper on a boat notices wave crests passing the anchor chain every 5 s. The skipper estimates the distance between crests is 15 m. What is the speed of the water waves?
3 m/s
Two tuning forks produce sounds of wavelengths 3.4 m and 3.3 m. What beat frequency is produced?
3.0 Hz
Radio waves travel at the speed of light, 300,000 km/s. The wavelength of a radio wave received at 100 MHz is
3.0 m
A bat chirps to locate a tasty lunch. The chirp travels at 340 m/s and its echo is heard 1 s after the chirp. Distance to the lunch is
340 m
A boat at anchor is rocked by waves whose crests are 40 m apart and with wave speed 10 m/s. These waves reach the boat once every
4.0 s
In Europe an electric razor completes 50 vibrations in 1 s. The frequency of these vibrations is
50 Hz with a period of 1/50 s
What beat frequency is produced when a 240-Hz and a 246-Hz tuning fork are sounded together?
6 Hz
A wave travels an average distance of 6 m in 1 s. What is the wave's velocity?
6 m/s
A 60 vibration per second wave travels 30 m in 1 s. Its frequency is
60 Hz and it travels at 30 m/s
The period of the second hand on a clock is
60 s
The fundamental frequency of a violin string is 440 Hz. The frequency of its second harmonic is
880 Hz
Does the conical angle of a shock wave open wider, narrow down, or remain constant as a supersonic aircraft increases its speed?
The conical angle of a shock wave becomes narrower with greater speeds.
Sound waves cannot travel in
a vacuum
A standing wave occurs when
a wave reflect upon itself
In perceiving its environment, a dolphin makes use of
all of the above
The Doppler effect is characteristic of
all of the above
Wave interference occurs for
all of the above
The vibrations of a longitudinal wave move in a direction
along the direction of wave travel
The loudness of a musical sound is a measure of the sound wave's
amplitude
A sonic boom can NOT be produced by
an aircraft flying slower than the speed of sound
The reflection of sound is
an echo
The least amount of energy is required to produce forced vibration in an object
at its natural frequency
The vibrations of a transverse wave move in a direction
at the right angles to the direction of wave travel
For light, a red shift indicates the light source moves
away from you
A dolphin perceives its environment by the sense of
both
A wave is a vibration in
both
Refraction of sound can occur in
both
The natural frequency of an object depends on its
both
Repeatedly tap the side of a drinking glass with a spoon while filling it with water and you will notice that the pitch of the sound
decreases
When sound travels faster higher above ground level than it does closer to the ground, sound bends
downward
A Doppler effect occurs when a source of sound moves
either (toward you or away from you)
Sound energy that is not reflected is
either or both
What moves from place to place in wave motion is
energy
A shock wave is produced when the speed of an object
exceeds the speed of sound in air
A bow wave is produced in water when the speed of an object
exceeds the speed of waves in water
High pitched sound has a high
frequency
The pitch of a musical sound depends on the sound wave's
frequency
When we consider how frequently a pendulum swings to and fro we're talking about its
frequency
The quality of a musical note has to do with its
harmonics
Sound travels fastest in
ice
Compressions and rarefactions normally travel
in the same direction in a wave
While at a concert, a wind blows directly from the orchestra toward you. The speed of the sound you hear is
increased
The phenomenon of beats results from sound
interference
If you double the frequency of a vibrating object, its period
is half
A sound wave is a
longitudinal wave
Compressions and rarefactions are characteristic of
longitudinal waves
The amplitude of a sound wave is closely related to
loudness
All other things being the same, strings having more mass than other strings will produce
lower frequency notes
A wave barrier is produced in water when the speed of an object
matches the speed of waves in water
A node is a position of
minimum amplitude
An explosion occurs 34 km away. For sound that travels at 340 m/s, you'll hear the explosion in
more than 20 s
Double the frequency of sound and you also double its
none of the above
A wave travels an average distance of 1 m in 1 s with a frequency of 1 Hz. Its amplitude is
not enough information
During a single period, the distance traveled by a wave is
one wavelength
When we consider the time taken for a pendulum to swing to and fro we're talking about the pendulum's
period
A sound source of high frequency emits a high
pitch
Which doesn't belong to the same family?
radio waves
Reverberation is a case of
re-echoed sound
Some singers are able to shatter a crystal chandelier with their voice, which illustrates
resonance
Troops break step when marching across a bridge to prevent
resonance
When you tune a radio to a certain station, you match the frequency of the internal electrical circuit to the frequency of that radio station, which illustrates
resonance
You dip your finger repeatedly into water and make waves. If you dip your finger more frequently, the wavelength of the waves
shortens
When the handle of a tuning fork is held solidly against a table, the sound becomes louder and the time the fork keeps vibrating becomes
shorter
Reverberation is a phenomenon you would likely to hear if you sing in the
shower
The object with the natural frequency of higher pitch is a
small bell
Which of the following is a longitudinal wave?
sound
Which of the following is not a transverse wave?
sound
A bass fiddle is louder than a harp because of its
sounding board
The explanation for all types of refraction involves a change in
speed
A compression is a squash and a rarefaction is a
stretch
On days when the air nearest the ground is colder than air above, sound waves
tend to be refracted downward
The speed of a sound wave in air depends on
the air temperature
In a longitudinal wave, the compressions and rarefactions travel in
the same direction
The medium in which a wave travels
transmits the wave
Sound waves can interfere with one another so that no sound is produced
true
When sound travels faster at ground level than higher in the air, sound tends to bend
upward
The source of all sounds is something that is
vibrating
The source of all wave motion is a
vibrating object
A wiggle in time is a
vibration
Sound travels faster when the air is
warm
In designing a music hall, an acoustical engineer is concerned with
wave interference