Chapter 17 Mechanical Waves and Sound-flashcards
1. A mechanical wave moves through a medium, which can be
Solid, liquid, both
2. Which type of mechanical wave needs a source of energy to produce it?
Transverse, longitudinal(compressional), both
3. Which wave causes the medium to vibrate only in a direction parallel to the wave’s motion?
Transverse, longitudinal, surface
4. When a surfer rides an ocean wave on her surfboard, she is actually riding on
Crest, trough, rest position
5. Find the frequency of 2 wavelengths in 1 second.
2 Hz, .5Hz, 1m/s
6. A period is the length of time it takes for
A disturbance to start, a wave to travel the length of the rope, one complete wavelength to pass a fixed point
7. To determine the speed of a wave, you would use which of the following formulas?
Speed = frequency x amplitude, speed = wavelength x frequency, speed = wavelength x period
8. A wave gas a wavelength of 10m and a frequency of 5Hz, find the speed.
50m/s, .5m/s. 2m/s
9. To find amplitude, measure
From trough to rest position, from crest to rest position, either one
10. To what is amplitude related?
Amount of energy carried by the wave, maximum displacement from the rest position, both
11. When a wave strikes a solid barrier, it behaves like a basketball hitting a backboard. This wave behavior is called reflection, refraction, diffraction
12. In refraction, when a wave travels from 1 medium to another, it
Changes speed, stays in step, travel in opposite directions
13. Suppose 2 waves collide and the temporary combined wave that results is smaller than the original waves. What term best describes this interaction?
Diffraction, constructive interference, destructive interference
14. A sound wave is an example of a
Transverse wave, longitudinal (compressional) wave, surface wave
15. In which medium does sound travel the fastest?
Water, air, cast iron
16. Sonar equipment sends sound waves into deep water and measures
Only the direction of the reflected wave, refraction of the transmitted wave, the time delay of the returning echo
17. A piano, violin, or guitar uses the resonance of a wooden soundboard to
Amplify the sound, dampen the sound, raise the pitch
18. An ambulance siren sounds different as it approaches you than when it moves away from you. What scientific term would you use?
Ultrasound, infrasound, Doppler effect
19. When a sound source approaches you, the pitch you hear is
Lower, higher, stays the same
20. You can make a wave in a rope by adding ? at one end of the rope.
Ribbons, energy, decibels
21. Instead of crests and troughs, a longitudinal wave has compressions and
Reflections, refractions, rarefactions
22. The trough of a transverse wave is most similar to a ? in a longitudinal wave.
Crest, compression, rarefaction
23. A wave in a rope is a transverse wave, but a sound wave is a
Compressional, surface, diffraction
24. Waves in a rope are transverse waves because the medium’s vibration is ? to the direction in which the wave travels. Parallel, perpendicular, magnetic
25. In a transverse wave, ? is measured from crest to crest or from trough to trough.
Period, frequency, wavelength
26. To determine the speed of a wave, you must know the wave’s wavelength and
Period, frequency, amplitude
27. If a wave has a wavelength of 4m and a frequency of 3 Hz, its speed is
1.3 m/s, 12 m/s, 7 m/s
28. To compare the energy of different waves, measure the ? of the waves.
Period, frequency, amplitude
29. If 2 waves collide and form a temporary larger wave, the interference is
Constructive, destructive, standing
30. The standard measure used to compare sound intensities is the
Decibel, hertz, meter
31. When a person plucks a string, the number of wavelengths determine the ? of the sound produced.
Amplitude, pitch, period
32. On a piano, striking strings with the hammer set up ?? between the strings and the soundboard.
Constructive, destructive, standing waves
33. When a train streaks by blowing its whistle, the changing pitch you hear is due to the
Dopper effect,standing waves, amplitude