# Waves Ch 2 Level 2

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1. 100 =
101 =
102 =
103 =
• 100 = 1
• 101 = 10
• 102 = 100
• 103 = 1000
2. 3dB =
Doubling the intensity
3. 6dB =
Increasing intensity by a factor of 4
4. 9dB =
Increasing intensity by a factor of 8
5. 10dB =
Increasing intensity by a factor of 10
6. -3dB =
Decreasing to 1/2 of the original intensity (decrease by a factor of 2)
7. -6dB =
Decreasing to 1/4 of the original intensity (decrease by a factor of 4)
8. -9dB =
Decreasing to 1/8 of the original intensity (decrease by a factor of 8)
9. -10dB =
Decreasing to 1/10 of the original intensity (decrease by a factor of 10)
10. The frequency is determined strictly by the wave _____.
The frequency is determined strictly by the wave source.
11. The period of a wave is determined strictly by the wave ______.
The period of a wave is determined strictly by the wave source.
12. The propagation velocity is determined strictly by the properties of the ______.
The propagation velocity is determined strictly by the properties of the medium.
13. The wave source cannot change the _________ _______ which is strictly determined by the properties of the ______.
The wave source cannot change the propagation velocity which is strictly determined by the properties of the medium.
14. The two properties of the medium which determine the propagation velocity are _____ (related to density) and ______ (related to compressibility and stiffness).
• The two properties of the medium which determine the propagation
• velocity are inertia (related to density) and elasticity (related to
• compressibility and stiffness).
15. The propagation velocity _____ with increased density, assuming no change in stiffness.
The propagation velocity decreases with increased density, assuming no change in stiffness.
16. As the density decreases, the propagation velocity ______, assuming no changes in stiffness.
As the density decreases, the propagation velocity increases, assuming no changes in stiffness.
17. As the stiffness increases, the propagation velocity ______.
As the stiffness increases, the propagation velocity increases.
18. A stiff material is not very elastic, so stiffness and elasticity are _______ related.
A stiff material is not very elastic, so stiffness and elasticity are inversely related.
19. A material which is inelastic is a stiff material, and therefore has a high ______ ______.
A material which is inelastic is a stiff material, and therefore has a high propagation velocity.
20. Inelasticity and incompressibility are related to _______.
Inelasticity and incompressibility are related to stiffness.
21. Elasticity and __________ are inversely related.
Elasticity and compressibility are inversely related.
22. A gas is generally more compressible than a _____ which is generally more compressible than a solid.
A gas is generally more compressible than a liquid which is generally more compressible than a solid.
23. Air is more compressible than bone and has a much ____ ________ ________.
Air is more compressible than bone and has a much lower propagation velocity.
24. _______ is sound below human hearing.
Infrasound is sound below human hearing.
25. _______ sound is sound within human hearing.
Audible sound is sound within human hearing.
26. ________ is sound above human hearing.
Ultrasound is sound above human hearing.
27. ________ ultrasound is approximately from 2 MHz to 10MHz.
Diagnostic ultrasound is approximately from 2 MHz to 10MHz.
28. All sound waves are ________ mechanical waves.
All sound waves are longitudinal mechanical waves.
29. Human hearing is approximately ___ to ___.
Human hearing is approximately 20Hz to 20kHz.
30. Infrasound is sound below ___.
Infrasound is sound below 20Hz.
31. Ultrasound is any sound above ___.
Ultrasound is any sound above 20kHz.
32. ______ is the rate at which energy is transferred.
Power is the rate at which energy is transferred.
33. ______ is proportional to the (amplitude)2.
Power is proportional to the (amplitude)2.
34. If the amplitude is doubled, the power is _________.
If the amplitude is doubled, the power is quadrupled.
35. If the amplitude is halved, the power is ________.
If the amplitude is halved, the power is quartered.
36. If the amplitude is increased by a factor of 2, the power is increased by a factor of _.
If the amplitude is increased by a factor of 2, the power is increased by a factor of 4.
37. If the amplitude is decreased by a factor of 2, the power is decreased by a factor of _.
If the amplitude is decreased by a factor of 2, the power is decreased by a factor of 4.
38. Power is measured in units of _____.
Power is measured in units of Watts.
39. The ______ is defined as the concentration of energy.
The intensity is defined as the concentration of energy.
40. The fundamental unit for ________ is power per area.
The fundamental unit for intensity is power per area.
41. If power is given in Watts and the area is given in ___, the intensity has units of Watts/cm2.
If power is given in Watts and the area is given in cm2, the intensity has units of Watts/cm2.
42. If the area is increased by a factor of two and the power is unchanged, the intensity is decreased by a factor of ___.
If the area is increased by a factor of two and the power is unchanged, the intensity is decreased by a factor of two.
43. If the power increases by a factor of two and the area is unchanged, the intensity ________ by a factor of ___.
If the power increases by a factor of two and the area is unchanged, the intensity increases by a factor of two.
44. If the power _____ by a factor of two and the area increases by a factor of two, the intensity does not _____.
If the power increases by a factor of two and the area increases by a factor of two, the intensity does not change.
45. If the amplitude doubles, the power _______. If the area does not change, the intensity also ________.
If the amplitude doubles, the power quadruples. If the area does not change, the intensity also quadruples.
46. Intensity is proportional to the _______2.
Intensity is proportional to the amplitude2.
47. The intensity is inversely proportional to the ____.
The intensity is inversely proportional to the area.
 Author: dorkfork ID: 234311 Card Set: Waves Ch 2 Level 2 Updated: 2013-09-18 16:31:42 Tags: ultrasound sound waves dorkfork Folders: Description: Ultrasound Physics and Instrumentation Show Answers: