Show:
Types of Waves
Wave Interactions & Ears
Wave Properties
Waves and Hearing
Miscellaneous
100
What most distinguishes mechanical waves from other types of waves?
Mechanical waves require a medium
100
How does bouncing off of a surface affect a wave’s speed?
The speed doesn't change.
100
If a wave passes by a point 120 times per minute, what is its frequency in hertz?
2 Hz
100
If a wave’s period is doubled, what happens to its frequency?
It is halved
100
If you create waves in a blanket by shaking it up and down, what type of waves are these?
transverse
200
In what type of wave is the medium displaced perpendicular to the direction that energy is traveling?
transverse wave
200
What is the name we give to the principle that explains why waves bend when passing at an angle from one medium into another?
refraction
200
If you walk your dog 3 times evenly spaced throughout an entire day, what is the period of dog walking?
8 hours
200
A 40 dB sound has 10 times the intensity of a 30 dB sound. A 30 dB sound has 1000 times the intensity of a 0 dB sound. How many times more intense is a 120 dB sound than an 80 dB sound?
10,000 times
200
What do you call the places on a standing wave where the medium is being displaced the most?
antinodes
300
Give an example of a surface wave.
(E.g., ocean wave)
300
What do we call the kind of waves caused when a wave interacts with its own reflection so it appears to stay in one place on a medium and not travel along that medium?
standing waves
300
What is the wavelength of a wave with a frequency of 10 cycles per second traveling at 20 meters per second?
2 m
300
Suppose a flutist plays their instrument covering holes so it vibrates 240 times per second. If they cover more holes, the note produced decreases in pitch. Are the standing waves in the air column inside the flute now shorter or longer?
longer
300
Put in order from slowest to fastest by letter: (a) the speed of a fighter jet as it takes off; (b) the speed of sound in air; (c) the speed of a plane breaking the sound barrier; (d) the speed of a bus on the freeway
d, a, b, c
400
What type of mechanical waves are sound waves?
longitudinal or compression
400
What separates the outer ear from the middle ear?
eardrum or tympanic membrane
400
How fast is a wave traveling if it has a wavelength of 12 centimeters and a frequency of 3 cycles per minute?
36 cm/min
400
What is the lowest approximate frequency a human can hear?
20 Hz
400
_________ is to loudness as frequency is to pitch
intensity
500
If a surface wave passes under a buoy, how does the buoy move?
In a circle
500
What are the three bones in the middle ear called?
hammer, anvil, stirrup
500
What happens to a sound wave’s wavelength when its frequency is increased?
The wavelength gets shorter
500
A speaker creates sounds by moving a magnet back and forth inside a something else. What is the magnet moved back and forth inside?
a coil of wire
500
Notes that are slightly higher pitched than they should be are called “sharp”; notes slightly lower than they should be are called “flat.” If someone singing along to their car radio sounds perfectly in key to the driver, will she sound sharp or flat to you as the car moves away from you?
flat