Conceptual Physics Ch 26 Test
In order for sound from a speaker to reach a listener, air near the speaker must travel to the listener.
false
A singer shattering a crystal glass with her voice is a demonstration of Echo Beats Resonance Interference?
resonance
The tacoma narrows bridge collapsed due to...
resonance
Sound waves are produced by )Radio stations )vibrating objects )soft objects?
vibrating objects
A 340Hz sound wave travels at 340 m/s in air, with a wavelength of ... 1 m 10 m 100 m
1 m
How many times more intense is a 80 dB sound than a 60 dB sound? 200 100 50
100
compared to a sound of 40 decibels, a sound of 60 decibels is? 20 times the intensity 100 times the intensity 200 times the intensity
100 times the intensity
compared to the threshold of hearing, a sound level of 30 decibels is? 10 times more intense 300 times more intense 30 times more intense 1000 times more intense
1000 times more intense
A general rule for finding the distance of lightening bolt is to count the number of seconds between seeing and hearing the bolt and divide by?
3
A sound wave that has a wavelength of 1 meters in room temp. air has a frequency of about... 340 Hz 680Hz 1020 Hz
340 Hz
A sound wave that has a wavelength of 1 meter in room-temperature air has a frequency of about 340Hz 680hz 1020hz None of these
340hz
You note a 2 second delay for an echo in a canyon. What is the distance to the wall of the canyon? 440hz 340hz 560hz
340hz
Two whistles produce sounds of wavelengths 3.4m and 3.3m. What is the beat frequency produced? .1Hz 1 Hz 2 Hz 3 Hz 4 Hz
4 Hz
How many times a minute will you be in step with a friend when you walk at 80 steps per minute and your friend walks at 75 steps per minutes? 155 80 75 5
5
Beats are produced when two tuning forks, one of frequency 240 Hz and the other frequency 246 Hz, are sounded together. The frequency of the beats is.. 6 Hz 12 Hz 240 Hz
6 Hz
The speed of sound in dry air at 20 degrees celcius is 340 m/s. How far away is a jet plane when you notice a 2 second delay between seeing the plane and hearin it? 6800m 680m 340m 40m
680 m
If you wished to produce a sound with a wavelength in air equal to the length of the room, 5m, what would be its frequency? 78hz 68hz 50hz 18hz
68hz
A tuning fork of frequency 200 Hz will resonate if a sound wave incident on it has a frequency of _____________? )100Hz )400Hz )Both 100 and 400
Both 100 and 400Hz
Sound waves can Interfere with one another so that no sound results true or false
False
Sound waves cannot travel in ______________. Air, water, vacuum, or all of the above?
a vacuum
Sound waves in air are a series of _______________? )Hi and low pressure regions, )periodic disturbances, )periodic conversion and rarefractions, )all of the above
all of the above
You are water skiing on a lake, and you are being pulled by a noisy motorboat. Another motorboat is speeding through the water a bit ahead of your boat so that rarefactions from its motor hit you when compressions from your boats motor hit you. you hear....
almost nothing due to destructive interference
Resonance occurs when...
an object is forced to vibrate at its natural frequency
When the handle of a tuning fork is held solidly against a table, the sound becomes louder and the length of time the fork vibrates Longer Shorter The same?
becomes shorter
Noise cancelling earphones are an example of
destructive interference
a pulse of compressed air that is part of a sound wave is a rarefaction
false
sound can travel through solids. liquids, gases, and even a vacuum.
false
the word "pitch" refers to the period of a sound wave
false
The speed of a sound wave depends on ________________. )Frequency )Wavelength )Air temp
frequency
Beats can be heard when two tuning forks.... )Are sounded together )have almost same frequency and are sounded together?
have almost the same frequency and are sounded together
In which one of the following does sound travel the fastest? Steam Water Ice
ice
The phenomenon of beats results from sound Refractions Reflection Interference All of the above
interference
If you are standing equally distant from two television sets that are emitting the exact same sound waves, the sound...
is louder because the waves constructively interfere.
A sound wave is a ________________. )Transverse wave )Standing wave )Longitudinal wave
longitudinal wave
If the sounding board were left out of a music box, the music box would make the same sound or not a sound at all?
not sound at all
Compared to the speed of light, sound travels Faster slower or about the same?
slower
Which of the following would be most likely to transmit sound with the highest speed? )Steel bridge )Water in a pool )Wood cabinet
steel in a bridge
almost everything that exists has a natural frequency.
true
even a steel bridge can collapse because of resonance.
true
if you strike a tuning fork and hold it on a table, the sound becomes relatively loud.
true
when an object is disturbed slightly and then left alone, its vibrates at its natural frequency.
true
when an object is forced to vibrate at its natural frequency, its vibration amplitude increases.
true
when an object is forced to vibrate at its natural frequency, resonance occurs.
true
Sound travels faster in air if the air is warm, cold or neither?
warm