# Waves Ch 2 Level 2

The flashcards below were created by user Anonymous on FreezingBlue Flashcards.

1. Pf= 1,000 Watts
Pi= 10 Watts
What is the change in the dB?
2. 100 =
101 =
102 =
103 =
• 100 = 1
• 101 = 10
• 102 = 100
• 103 = 1000
3. 3dB =
Doubling the intensity
4. 6dB =
Increasing intensity by a factor of 4
5. 9dB =
Increasing intensity by a factor of 8
6. 10dB =
Increasing intensity by a factor of 10
7. -3dB =
Decreasing to 1/2 of the original intensity (decrease by a factor of 2)
8. -6dB =
Decreasing to 1/4 of the original intensity (decrease by a factor of 4)
9. -9dB =
Decreasing to 1/8 of the original intensity (decrease by a factor of 8)
10. -10dB =
Decreasing to 1/10 of the original intensity (decrease by a factor of 10)
11. The frequency is determined strictly the the wave _____.
The frequency is determined strictly the the wave source.
12. The period of a wave is determined strictly by the wave ______.
The period of a wave is determined strictly by the wave source.
13. The propagation velocity is determined strictly by the properties of the ______.
The propagation velocity is determined strictly by the properties of the medium.
14. 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.
15. 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).
16. The propagation velocity _____ with increased density, assuming no change in stiffness.
The propagation velocity decreases with increased density, assuming no change in stiffness.
17. 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.
18. As the stiffness increases, the propagation velocity ______.
As the stiffness increases, the propagation velocity increases.
19. 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.
20. 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.
21. Inelasticity and incompressibility are related to _______.
Inelasticity and incompressibility are related to stiffness.
22. Elasticity and __________ are inversely related.
Elasticity and compressibility are inversely related.
23. 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.
24. Air is more compressible than bone and has a much ____ ________ ________.
Air is more compressible than bone and has a much lower propagation velocity.
25. _______ is sound below human hearing.
Infrasound is sound below human hearing.
26. _______ sound is sound within human hearing.
Audible sound is sound within human hearing.
27. ________ is sound above human hearing.
Ultrasound is sound above human hearing.
28. ________ ultrasound is approximately from 2 MHz to 10MHz.
Diagnostic ultrasound is approximately from 2 MHz to 10MHz.
29. All sound waves are ________ mechanical waves.
All sound waves are longitudinal mechanical waves.
30. Human hearing is approximately ___ to ___.
Human hearing is approximately 20Hz to 20kHz.
31. Infrasound is sound below ___.
Infrasound is sound below 20Hz.
32. Ultrasound is any sound above ___.
Ultrasound is any sound above 20kHz.
 Author: Anonymous ID: 234234 Card Set: Waves Ch 2 Level 2 Updated: 2013-09-11 17:55:43 Tags: sound waves ultrasound dorkfork Folders: Description: Ultrasound Physics & Instrumentation Show Answers: