1
The low points on a wave are called __________.
troughs
Give an example of a medium.
Air, water, wood, steam, etc...
What is thunder?
The sound of lightning
The high points on a wave are called ____________.
True or false: the more energy a wave has, the greater its amplitude.
true
What does oscillate mean?
Vibration back and forth.
What type of medium does sound move the slowest?
Gas
What part of your middle ear vibrates?
ear drum
True or false: The lower the temperature, the faster sound travels
false - the higher the temperature, the faster
The distance from rest to a crest is called the _______________.
amplitude
True or false: Sound can move through any medium.
true
The unit for frequency is the ______________
Hz (Hertz)
What does Mach mean?
It's the speed unit of sound
When lightning strikes, why is there a delay before you hear the thunder?
Light travels WAY faster than sound.
What is a mechanical wave?
a disturbance in matter that transfers energy through that matter
Wavelengths are measured in ___________.
meters
What does your outer ear do to sound?
it channels it to your middle ear
What is a surface wave?
A wave that travels along the surface of a medium.
The distance between the top of one crest to the top of the next crest is called a _________________.
wavelength
What is supersonic speed?
Speed that is faster than sound.
What Mach is the fastest any man-made object has ever traveled in our atmosphere?
Mach 2
Define frequency.
The number of complete cycles (wavelengths) in a given amount of time.
Does sound travel faster through dry air at 32o F or dry air at 55o F? And why?
55o F because it's warmer and sound travels faster through higher temperatures
Give an example of a longitudinal wave.
Slinky
How does the amplitude of a wave relate to the wave's energy?
increased amplitude = increased energy
What does your inner ear do with sound waves?
sends signals to your brain
What is the indication of how high or low a sound is called?
pitch
In our lab with the laser, explain how we "saw" sound waves.
The sound waves made the balloon vibrate, which made the laser pointed on the mirror on the balloon to vibrate.
True or false: Intensity and loudness are the same thing.
False - intensity measures the energy (amplitude), loudness is the physical response to the intensity
In a transverse wave, the medium vibrates ______________ (what direction?) to the direction of the wave.
perpendicular
low pitch = __________ (high or low) frequency
low
In a longitudinal wave, the medium vibrates ______________ (what direction?) to the direction of the wave.
parallel
Between 20 and 20,000 Hz are called ___________ waves.
sonic
high pitch = __________ (high or low) frequency
high
Explain why the ISS can travel 17,770 mph?
There is no air resistance in space.
Give an everyday example of frequency.
Wading in the water at the beach. How often do the waves hit you?
What is the threshold of human hearing? Remember the units!
0 dB
Wavelength and frequency are inversely proportional. What does inversely proportional mean?
Wavelength increases, frequency decreases
Wavelength decreases, frequency increses
What does the Doppler effect sound like?
rrrRRREEEeeerrr
What is the scientific name for your ear drum?
tympanic membrane
What is the speed of sound in mph?
761mph
What type of waves are surface waves?
transverse and longitudinal
Pitch is determined by the _____________ of a sound wave.
frequency
Does sound travel faster through iron or salt water? Why?
Iron because the molecules in iron are closer together than those in salt water.
Anything above 20,000 Hz is called _____________.
ultrasonic
Physical damage can occur to the human ear at _________ dB.
120
Human ears can hear between ______ Hz and _________ Hz.
20
20,000
Anything below 20 Hz is called ___________.
Infrasonic
In our lab with the different size bottles, explain why the large bottle had a low pitch and the smallest bottle had a high pitch.
The sound wave frequency in the large bottle was smaller than the sound wave frequency in the smallest bottle.