Physical Science Ch 18 Test Review

1. a megaphone amplifies sound by focusing sound energy into one specific ____.
2. Vocal cords are stretched across the upper portion of the _____.
5. In which structure do vibrations in a liquid transfer energy to thousands of sensory hair cells?
8. the quality of an instrument also depends on the _____ its made from and manner of play
12. children can hear higher frequencies than adults
13. which ear structure converts acoustic energy to kinetic energy by vibrating?
14. During speaking or singing, the vocal cords _____ and the glottis is partially closed.
15. a region of a sound wave with low particle density.
16. Robert Boyle found that an alarm watch in a ______ did not make a sound.
19. unit measurement of loudness of sound
21. how high or low a tone sounds is __________
23. The eustachian tube helps to equalize the ______ on both sides of the eardrum.
26. Acoustic amplification is the process of making a sound _____
27. the quality of sound from fundamental and overtones
29. Sound waves are transmitted by alternating regions of high and low _______.

1. muscle that controls the volume of air that passes over the vocal cords
3. three bones of the middle ear: hammer, stirrup, ____
4. sound will travel the fastest in which type of substance
6. Which nerve relays sensory signals to the brain?
7. Different pitches travel at _______ speeds.
9. Loudness is most closely related to the __________ of a sound wave.
10. the measure of power of a soundwave
11. A whole-number multiple of a fundamental frequency is called ____
17. Frequencies _____ the range of human hearing are known as ultrasonic waves.
18. this type of waves can be applied to echolocation, medical imaging and nondestructive testing
20. the slowest medium in which sound travels
22. The part of the ear that helps us determine the direction of a sound’s source.
24. An increase from 40 to 60dB to one______-fold
25. what determines a sound’s pitch?
28. demonstrated that sound needs a medium through which to travel