# How things work college course/Waves (Physics Classroom)/Testbank

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## Waves_Physics_classroom

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### Waves_Physics_classroom-v1s1

1. A dense rope is connected to a rope with less density (i.e. fewer kilograms per meter). If the rope is stretched and a wave is sent along high density rope,
    ___ a) the low density rope supports a wave with a higher speed
    ___ b) the low density rope supports a wave with a lower frequency
    ___ c) the low density rope supports a wave with a higher frequency
    ___ d) the low density rope supports a wave with a lower speed
2. Two signals (dashed) add to a solid
    ___ a) dissonance
    ___ b) fifth
    ___ c) octave
3. These two pulses will collide and produce
    ___ a) negative interference
    ___ b) positive interference
    ___ c) positive diffraction
    ___ d) negative diffraction
4. If you start moving towards a source of sound, the pitch becomes
    ___ a) higher
    ___ b) unchanged
    ___ c) lower
5. Two signals (dashed) add to a solid
    ___ a) fifth
    ___ b) octave
    ___ c) dissonance
6. When a wave is reflected off a stationary barrier, the reflected wave
    ___ a) has higher frequency than the incident wave
    ___ b) has lower amplitude than the incident wave
    ___ c) both of these are true
7. What happens to the wavelength on a wave on a stretched string if the wave passes from lightweight (low density) region of the rope to a heavy (high density) rope?
    ___ a) the wavelength gets longer
    ___ b) the wavelength stays the same
    ___ c) the wavelength gets shorter
8. Why don't we hear beats when two different notes on a piano are played at the same time?
    ___ a) The beats happen so many times per second you can't hear them.
    ___ b) Reverberation usually stifles the beats
    ___ c) Echo usually stifles the beats
    ___ d) The note is over by the time the first beat is heard
9. A tuning fork with a frequency of 440 Hz is played simultaneously with a tuning fork of 442 Hz. How many beats are heard in 10 seconds?
    ___ a) 50
    ___ b) 60
    ___ c) 20
    ___ d) 40
    ___ e) 30
10. Comparing a typical church to a professional baseball stadium, the church is likely to have
    ___ a) reverberation instead of echo
    ___ b) echo instead of reverberation
    ___ c) both reverberation and echo
    ___ d) neither reverberation nor echo
11. Why do rough walls give a concert hall a “fuller” sound, compared to smooth walls?
    ___ a) The difference in path lengths creates more reverberation.
    ___ b) Rough walls make for a louder sound.
    ___ c) The difference in path lengths creates more echo.
12. If a source of sound is moving towards you, the pitch becomes
    ___ a) unchanged
    ___ b) higher
    ___ c) lower
13. These two pulses will collide and produce
    ___ a) positive interference
    ___ b) negative diffraction
    ___ c) positive diffraction
    ___ d) negative interference
14. Two signals (dashed) add to a solid
    ___ a) dissonance
    ___ b) fifth
    ___ c) octave
15. People don't usually perceive an echo when
    ___ a) it takes more than a tenth of a second after the original sound to arrive
    ___ b) it arrives less than a tenth of a second after the original sound
    ___ c) it arrives at a lower pitch
    ___ d) it arrives at exactly the same pitch
    ___ e) it arrives at a higher pitch
16. These two pulses will collide and produce
    ___ a) negative interference
    ___ b) positive interference
    ___ c) positive diffraction
    ___ d) negative diffraction

#### Key to Waves_Physics_classroom-v1s1

1. A dense rope is connected to a rope with less density (i.e. fewer kilograms per meter). If the rope is stretched and a wave is sent along high density rope,
       + a) the low density rope supports a wave with a higher speed
       - b) the low density rope supports a wave with a lower frequency
       - c) the low density rope supports a wave with a higher frequency
       - d) the low density rope supports a wave with a lower speed
2. Two signals (dashed) add to a solid
       - a) dissonance
       + b) fifth
       - c) octave
3. These two pulses will collide and produce
       + a) negative interference
       - b) positive interference
       - c) positive diffraction
       - d) negative diffraction
4. If you start moving towards a source of sound, the pitch becomes
       + a) higher
       - b) unchanged
       - c) lower
5. Two signals (dashed) add to a solid
       - a) fifth
       + b) octave
       - c) dissonance
6. When a wave is reflected off a stationary barrier, the reflected wave
       - a) has higher frequency than the incident wave
       + b) has lower amplitude than the incident wave
       - c) both of these are true
7. What happens to the wavelength on a wave on a stretched string if the wave passes from lightweight (low density) region of the rope to a heavy (high density) rope?
       + a) the wavelength gets longer
       - b) the wavelength stays the same
       - c) the wavelength gets shorter
8. Why don't we hear beats when two different notes on a piano are played at the same time?
       + a) The beats happen so many times per second you can't hear them.
       - b) Reverberation usually stifles the beats
       - c) Echo usually stifles the beats
       - d) The note is over by the time the first beat is heard
9. A tuning fork with a frequency of 440 Hz is played simultaneously with a tuning fork of 442 Hz. How many beats are heard in 10 seconds?
       - a) 50
       - b) 60
       + c) 20
       - d) 40
       - e) 30
10. Comparing a typical church to a professional baseball stadium, the church is likely to have
       + a) reverberation instead of echo
       - b) echo instead of reverberation
       - c) both reverberation and echo
       - d) neither reverberation nor echo
11. Why do rough walls give a concert hall a “fuller” sound, compared to smooth walls?
       + a) The difference in path lengths creates more reverberation.
       - b) Rough walls make for a louder sound.
       - c) The difference in path lengths creates more echo.
12. If a source of sound is moving towards you, the pitch becomes
       - a) unchanged
       + b) higher
       - c) lower
13. These two pulses will collide and produce
       + a) positive interference
       - b) negative diffraction
       - c) positive diffraction
       - d) negative interference
14. Two signals (dashed) add to a solid
       + a) dissonance
       - b) fifth
       - c) octave
15. People don't usually perceive an echo when
       - a) it takes more than a tenth of a second after the original sound to arrive
       + b) it arrives less than a tenth of a second after the original sound
       - c) it arrives at a lower pitch
       - d) it arrives at exactly the same pitch
       - e) it arrives at a higher pitch
16. These two pulses will collide and produce
       - a) negative interference
       + b) positive interference
       - c) positive diffraction
       - d) negative diffraction

### Waves_Physics_classroom-v2s1

1. A tuning fork with a frequency of 440 Hz is played simultaneously with a tuning fork of 442 Hz. How many beats are heard in 10 seconds?
    ___ a) 50
    ___ b) 60
    ___ c) 20
    ___ d) 30
    ___ e) 40
2. People don't usually perceive an echo when
    ___ a) it takes more than a tenth of a second after the original sound to arrive
    ___ b) it arrives at a lower pitch
    ___ c) it arrives at exactly the same pitch
    ___ d) it arrives at a higher pitch
    ___ e) it arrives less than a tenth of a second after the original sound
3. What happens to the wavelength on a wave on a stretched string if the wave passes from lightweight (low density) region of the rope to a heavy (high density) rope?
    ___ a) the wavelength stays the same
    ___ b) the wavelength gets shorter
    ___ c) the wavelength gets longer
4. Why don't we hear beats when two different notes on a piano are played at the same time?
    ___ a) The note is over by the time the first beat is heard
    ___ b) Reverberation usually stifles the beats
    ___ c) The beats happen so many times per second you can't hear them.
    ___ d) Echo usually stifles the beats
5. If a source of sound is moving towards you, the pitch becomes
    ___ a) unchanged
    ___ b) higher
    ___ c) lower
6. Comparing a typical church to a professional baseball stadium, the church is likely to have
    ___ a) reverberation instead of echo
    ___ b) echo instead of reverberation
    ___ c) neither reverberation nor echo
    ___ d) both reverberation and echo
7. Two signals (dashed) add to a solid
    ___ a) octave
    ___ b) dissonance
    ___ c) fifth
8. When a wave is reflected off a stationary barrier, the reflected wave
    ___ a) both of these are true
    ___ b) has higher frequency than the incident wave
    ___ c) has lower amplitude than the incident wave
9. If you start moving towards a source of sound, the pitch becomes
    ___ a) unchanged
    ___ b) higher
    ___ c) lower
10. These two pulses will collide and produce
    ___ a) positive diffraction
    ___ b) negative diffraction
    ___ c) positive interference
    ___ d) negative interference
11. Two signals (dashed) add to a solid
    ___ a) octave
    ___ b) dissonance
    ___ c) fifth
12. Why do rough walls give a concert hall a “fuller” sound, compared to smooth walls?
    ___ a) The difference in path lengths creates more reverberation.
    ___ b) Rough walls make for a louder sound.
    ___ c) The difference in path lengths creates more echo.
13. These two pulses will collide and produce
    ___ a) negative diffraction
    ___ b) positive interference
    ___ c) negative interference
    ___ d) positive diffraction
14. A dense rope is connected to a rope with less density (i.e. fewer kilograms per meter). If the rope is stretched and a wave is sent along high density rope,
    ___ a) the low density rope supports a wave with a lower frequency
    ___ b) the low density rope supports a wave with a higher speed
    ___ c) the low density rope supports a wave with a lower speed
    ___ d) the low density rope supports a wave with a higher frequency
15. These two pulses will collide and produce
    ___ a) positive interference
    ___ b) negative interference
    ___ c) positive diffraction
    ___ d) negative diffraction
16. Two signals (dashed) add to a solid
    ___ a) fifth
    ___ b) dissonance
    ___ c) octave

#### Key to Waves_Physics_classroom-v2s1

1. A tuning fork with a frequency of 440 Hz is played simultaneously with a tuning fork of 442 Hz. How many beats are heard in 10 seconds?
       - a) 50
       - b) 60
       + c) 20
       - d) 30
       - e) 40
2. People don't usually perceive an echo when
       - a) it takes more than a tenth of a second after the original sound to arrive
       - b) it arrives at a lower pitch
       - c) it arrives at exactly the same pitch
       - d) it arrives at a higher pitch
       + e) it arrives less than a tenth of a second after the original sound
3. What happens to the wavelength on a wave on a stretched string if the wave passes from lightweight (low density) region of the rope to a heavy (high density) rope?
       - a) the wavelength stays the same
       - b) the wavelength gets shorter
       + c) the wavelength gets longer
4. Why don't we hear beats when two different notes on a piano are played at the same time?
       - a) The note is over by the time the first beat is heard
       - b) Reverberation usually stifles the beats
       + c) The beats happen so many times per second you can't hear them.
       - d) Echo usually stifles the beats
5. If a source of sound is moving towards you, the pitch becomes
       - a) unchanged
       + b) higher
       - c) lower
6. Comparing a typical church to a professional baseball stadium, the church is likely to have
       + a) reverberation instead of echo
       - b) echo instead of reverberation
       - c) neither reverberation nor echo
       - d) both reverberation and echo
7. Two signals (dashed) add to a solid
       - a) octave
       - b) dissonance
       + c) fifth
8. When a wave is reflected off a stationary barrier, the reflected wave
       - a) both of these are true
       - b) has higher frequency than the incident wave
       + c) has lower amplitude than the incident wave
9. If you start moving towards a source of sound, the pitch becomes
       - a) unchanged
       + b) higher
       - c) lower
10. These two pulses will collide and produce
       - a) positive diffraction
       - b) negative diffraction
       + c) positive interference
       - d) negative interference
11. Two signals (dashed) add to a solid
       - a) octave
       + b) dissonance
       - c) fifth
12. Why do rough walls give a concert hall a “fuller” sound, compared to smooth walls?
       + a) The difference in path lengths creates more reverberation.
       - b) Rough walls make for a louder sound.
       - c) The difference in path lengths creates more echo.
13. These two pulses will collide and produce
       - a) negative diffraction
       + b) positive interference
       - c) negative interference
       - d) positive diffraction
14. A dense rope is connected to a rope with less density (i.e. fewer kilograms per meter). If the rope is stretched and a wave is sent along high density rope,
       - a) the low density rope supports a wave with a lower frequency
       + b) the low density rope supports a wave with a higher speed
       - c) the low density rope supports a wave with a lower speed
       - d) the low density rope supports a wave with a higher frequency
15. These two pulses will collide and produce
       - a) positive interference
       + b) negative interference
       - c) positive diffraction
       - d) negative diffraction
16. Two signals (dashed) add to a solid
       - a) fifth
       - b) dissonance
       + c) octave

### Waves_Physics_classroom-v1s2

1. These two pulses will collide and produce
    ___ a) positive diffraction
    ___ b) negative diffraction
    ___ c) negative interference
    ___ d) positive interference
2. What happens to the wavelength on a wave on a stretched string if the wave passes from lightweight (low density) region of the rope to a heavy (high density) rope?
    ___ a) the wavelength stays the same
    ___ b) the wavelength gets shorter
    ___ c) the wavelength gets longer
3. Two signals (dashed) add to a solid
    ___ a) octave
    ___ b) dissonance
    ___ c) fifth
4. Why don't we hear beats when two different notes on a piano are played at the same time?
    ___ a) The note is over by the time the first beat is heard
    ___ b) Echo usually stifles the beats
    ___ c) Reverberation usually stifles the beats
    ___ d) The beats happen so many times per second you can't hear them.
5. Why do rough walls give a concert hall a “fuller” sound, compared to smooth walls?
    ___ a) The difference in path lengths creates more reverberation.
    ___ b) Rough walls make for a louder sound.
    ___ c) The difference in path lengths creates more echo.
6. These two pulses will collide and produce
    ___ a) positive interference
    ___ b) negative diffraction
    ___ c) negative interference
    ___ d) positive diffraction
7. People don't usually perceive an echo when
    ___ a) it arrives at a lower pitch
    ___ b) it arrives at a higher pitch
    ___ c) it arrives less than a tenth of a second after the original sound
    ___ d) it arrives at exactly the same pitch
    ___ e) it takes more than a tenth of a second after the original sound to arrive
8. If a source of sound is moving towards you, the pitch becomes
    ___ a) lower
    ___ b) higher
    ___ c) unchanged
9. A tuning fork with a frequency of 440 Hz is played simultaneously with a tuning fork of 442 Hz. How many beats are heard in 10 seconds?
    ___ a) 50
    ___ b) 40
    ___ c) 30
    ___ d) 60
    ___ e) 20
10. These two pulses will collide and produce
    ___ a) negative interference
    ___ b) positive interference
    ___ c) negative diffraction
    ___ d) positive diffraction
11. Two signals (dashed) add to a solid
    ___ a) octave
    ___ b) dissonance
    ___ c) fifth
12. Comparing a typical church to a professional baseball stadium, the church is likely to have
    ___ a) both reverberation and echo
    ___ b) neither reverberation nor echo
    ___ c) echo instead of reverberation
    ___ d) reverberation instead of echo
13. A dense rope is connected to a rope with less density (i.e. fewer kilograms per meter). If the rope is stretched and a wave is sent along high density rope,
    ___ a) the low density rope supports a wave with a higher frequency
    ___ b) the low density rope supports a wave with a lower frequency
    ___ c) the low density rope supports a wave with a higher speed
    ___ d) the low density rope supports a wave with a lower speed
14. Two signals (dashed) add to a solid
    ___ a) dissonance
    ___ b) octave
    ___ c) fifth
15. If you start moving towards a source of sound, the pitch becomes
    ___ a) higher
    ___ b) unchanged
    ___ c) lower
16. When a wave is reflected off a stationary barrier, the reflected wave
    ___ a) has higher frequency than the incident wave
    ___ b) has lower amplitude than the incident wave
    ___ c) both of these are true

#### Key to Waves_Physics_classroom-v1s2

1. These two pulses will collide and produce
       - a) positive diffraction
       - b) negative diffraction
       - c) negative interference
       + d) positive interference
2. What happens to the wavelength on a wave on a stretched string if the wave passes from lightweight (low density) region of the rope to a heavy (high density) rope?
       - a) the wavelength stays the same
       - b) the wavelength gets shorter
       + c) the wavelength gets longer
3. Two signals (dashed) add to a solid
       - a) octave
       - b) dissonance
       + c) fifth
4. Why don't we hear beats when two different notes on a piano are played at the same time?
       - a) The note is over by the time the first beat is heard
       - b) Echo usually stifles the beats
       - c) Reverberation usually stifles the beats
       + d) The beats happen so many times per second you can't hear them.
5. Why do rough walls give a concert hall a “fuller” sound, compared to smooth walls?
       + a) The difference in path lengths creates more reverberation.
       - b) Rough walls make for a louder sound.
       - c) The difference in path lengths creates more echo.
6. These two pulses will collide and produce
       + a) positive interference
       - b) negative diffraction
       - c) negative interference
       - d) positive diffraction
7. People don't usually perceive an echo when
       - a) it arrives at a lower pitch
       - b) it arrives at a higher pitch
       + c) it arrives less than a tenth of a second after the original sound
       - d) it arrives at exactly the same pitch
       - e) it takes more than a tenth of a second after the original sound to arrive
8. If a source of sound is moving towards you, the pitch becomes
       - a) lower
       + b) higher
       - c) unchanged
9. A tuning fork with a frequency of 440 Hz is played simultaneously with a tuning fork of 442 Hz. How many beats are heard in 10 seconds?
       - a) 50
       - b) 40
       - c) 30
       - d) 60
       + e) 20
10. These two pulses will collide and produce
       + a) negative interference
       - b) positive interference
       - c) negative diffraction
       - d) positive diffraction
11. Two signals (dashed) add to a solid
       + a) octave
       - b) dissonance
       - c) fifth
12. Comparing a typical church to a professional baseball stadium, the church is likely to have
       - a) both reverberation and echo
       - b) neither reverberation nor echo
       - c) echo instead of reverberation
       + d) reverberation instead of echo
13. A dense rope is connected to a rope with less density (i.e. fewer kilograms per meter). If the rope is stretched and a wave is sent along high density rope,
       - a) the low density rope supports a wave with a higher frequency
       - b) the low density rope supports a wave with a lower frequency
       + c) the low density rope supports a wave with a higher speed
       - d) the low density rope supports a wave with a lower speed
14. Two signals (dashed) add to a solid
       + a) dissonance
       - b) octave
       - c) fifth
15. If you start moving towards a source of sound, the pitch becomes
       + a) higher
       - b) unchanged
       - c) lower
16. When a wave is reflected off a stationary barrier, the reflected wave
       - a) has higher frequency than the incident wave
       + b) has lower amplitude than the incident wave
       - c) both of these are true

### Waves_Physics_classroom-v2s2

1. If a source of sound is moving towards you, the pitch becomes
    ___ a) unchanged
    ___ b) lower
    ___ c) higher
2. A dense rope is connected to a rope with less density (i.e. fewer kilograms per meter). If the rope is stretched and a wave is sent along high density rope,
    ___ a) the low density rope supports a wave with a higher speed
    ___ b) the low density rope supports a wave with a lower frequency
    ___ c) the low density rope supports a wave with a higher frequency
    ___ d) the low density rope supports a wave with a lower speed
3. Two signals (dashed) add to a solid
    ___ a) octave
    ___ b) fifth
    ___ c) dissonance
4. These two pulses will collide and produce
    ___ a) positive interference
    ___ b) negative interference
    ___ c) positive diffraction
    ___ d) negative diffraction
5. People don't usually perceive an echo when
    ___ a) it takes more than a tenth of a second after the original sound to arrive
    ___ b) it arrives at a lower pitch
    ___ c) it arrives at exactly the same pitch
    ___ d) it arrives less than a tenth of a second after the original sound
    ___ e) it arrives at a higher pitch
6. Why do rough walls give a concert hall a “fuller” sound, compared to smooth walls?
    ___ a) Rough walls make for a louder sound.
    ___ b) The difference in path lengths creates more echo.
    ___ c) The difference in path lengths creates more reverberation.
7. These two pulses will collide and produce
    ___ a) positive diffraction
    ___ b) positive interference
    ___ c) negative interference
    ___ d) negative diffraction
8. Two signals (dashed) add to a solid
    ___ a) fifth
    ___ b) dissonance
    ___ c) octave
9. Two signals (dashed) add to a solid
    ___ a) fifth
    ___ b) octave
    ___ c) dissonance
10. What happens to the wavelength on a wave on a stretched string if the wave passes from lightweight (low density) region of the rope to a heavy (high density) rope?
    ___ a) the wavelength gets shorter
    ___ b) the wavelength gets longer
    ___ c) the wavelength stays the same
11. Comparing a typical church to a professional baseball stadium, the church is likely to have
    ___ a) neither reverberation nor echo
    ___ b) both reverberation and echo
    ___ c) reverberation instead of echo
    ___ d) echo instead of reverberation
12. These two pulses will collide and produce
    ___ a) positive interference
    ___ b) positive diffraction
    ___ c) negative interference
    ___ d) negative diffraction
13. A tuning fork with a frequency of 440 Hz is played simultaneously with a tuning fork of 442 Hz. How many beats are heard in 10 seconds?
    ___ a) 60
    ___ b) 20
    ___ c) 30
    ___ d) 40
    ___ e) 50
14. Why don't we hear beats when two different notes on a piano are played at the same time?
    ___ a) The beats happen so many times per second you can't hear them.
    ___ b) Reverberation usually stifles the beats
    ___ c) The note is over by the time the first beat is heard
    ___ d) Echo usually stifles the beats
15. If you start moving towards a source of sound, the pitch becomes
    ___ a) lower
    ___ b) higher
    ___ c) unchanged
16. When a wave is reflected off a stationary barrier, the reflected wave
    ___ a) both of these are true
    ___ b) has lower amplitude than the incident wave
    ___ c) has higher frequency than the incident wave

#### Key to Waves_Physics_classroom-v2s2

1. If a source of sound is moving towards you, the pitch becomes
       - a) unchanged
       - b) lower
       + c) higher
2. A dense rope is connected to a rope with less density (i.e. fewer kilograms per meter). If the rope is stretched and a wave is sent along high density rope,
       + a) the low density rope supports a wave with a higher speed
       - b) the low density rope supports a wave with a lower frequency
       - c) the low density rope supports a wave with a higher frequency
       - d) the low density rope supports a wave with a lower speed
3. Two signals (dashed) add to a solid
       - a) octave
       - b) fifth
       + c) dissonance
4. These two pulses will collide and produce
       - a) positive interference
       + b) negative interference
       - c) positive diffraction
       - d) negative diffraction
5. People don't usually perceive an echo when
       - a) it takes more than a tenth of a second after the original sound to arrive
       - b) it arrives at a lower pitch
       - c) it arrives at exactly the same pitch
       + d) it arrives less than a tenth of a second after the original sound
       - e) it arrives at a higher pitch
6. Why do rough walls give a concert hall a “fuller” sound, compared to smooth walls?
       - a) Rough walls make for a louder sound.
       - b) The difference in path lengths creates more echo.
       + c) The difference in path lengths creates more reverberation.
7. These two pulses will collide and produce
       - a) positive diffraction
       + b) positive interference
       - c) negative interference
       - d) negative diffraction
8. Two signals (dashed) add to a solid
       + a) fifth
       - b) dissonance
       - c) octave
9. Two signals (dashed) add to a solid
       - a) fifth
       + b) octave
       - c) dissonance
10. What happens to the wavelength on a wave on a stretched string if the wave passes from lightweight (low density) region of the rope to a heavy (high density) rope?
       - a) the wavelength gets shorter
       + b) the wavelength gets longer
       - c) the wavelength stays the same
11. Comparing a typical church to a professional baseball stadium, the church is likely to have
       - a) neither reverberation nor echo
       - b) both reverberation and echo
       + c) reverberation instead of echo
       - d) echo instead of reverberation
12. These two pulses will collide and produce
       + a) positive interference
       - b) positive diffraction
       - c) negative interference
       - d) negative diffraction
13. A tuning fork with a frequency of 440 Hz is played simultaneously with a tuning fork of 442 Hz. How many beats are heard in 10 seconds?
       - a) 60
       + b) 20
       - c) 30
       - d) 40
       - e) 50
14. Why don't we hear beats when two different notes on a piano are played at the same time?
       + a) The beats happen so many times per second you can't hear them.
       - b) Reverberation usually stifles the beats
       - c) The note is over by the time the first beat is heard
       - d) Echo usually stifles the beats
15. If you start moving towards a source of sound, the pitch becomes
       - a) lower
       + b) higher
       - c) unchanged
16. When a wave is reflected off a stationary barrier, the reflected wave
       - a) both of these are true
       + b) has lower amplitude than the incident wave
       - c) has higher frequency than the incident wave

   ##### Attribution (for quiz questions) under CC-by-SA license

    http://en.wikiversity.org/wiki/How_things_work_college_course/Waves_(Physics_Classroom)

   ##### Study guide

    http://www.physicsclassroom.com/class/waves