Sound facts
Amplitude of a sound determines what
How loud it is and the vibrations the sound makes
Difference in ultrasonic waves and infrasonic waves
US waves >20,000 Hz
IS waves < 20Hz
What does it mean to travel at Mach 3
traveling 3 times faster than the speed of sound in the air
Wave with a long wavelength
Sound
Pitch
An indication of how high or low a sound is, which is primarily determined by the frequency of the sound wave
Jets only travel over Mach 1 in sparsely populated areas. Why?
Damage to buildings and health of humans
Why does sound travel better in water than air
It travels 3x faster in liquid than in air
Mathematically what happens to frequency of wave when wavelength increased
F= 30/5
F=30/6
Frequency decreases
A wave with low pitch has a short or long wave
long
Supersonic Speed
Any speed that is faster than the speed of sound in the substance of interest
Using doppler Effect, what happens to sound wave as car is approaching you? Explain wavelength, frequency, pitch)
Sound bunched up. decreased WL, ^F, ^P
Speed of sound depends on what
Temperature
How fast sound travels through air if it is 40*C? Round to 2 decimal points.
v=331.5 + 0.6(40)
v= 355.50 m/sec
Amplitude of a wave is small, is crest tall or short
short
Sonic Boom
The sound produced as a result of an object traveling at or above Mach 1
Distance equals
speed x time
Which faster: Speed of sound in air or speed of light in air. Give example to prove.
light. we see lightning strike before we hear thunder and they occur at the same time
New windshield in car will break if sound of 4500Hz next to them. Neighbor practicing opera. Produces sound with a wavelength of .035 meters and it is 31*C. Will windshield break? Round answer to 2 decimal points.
v=331.5 + 0.6(31)
v=350.1 m/sec
F= 350.1m/sec / .035m
F=10,002.85 Hz
Yes
Machine makes sound wave loud and lots energy. Describe wave (wavelength, frequency, amplitude, pitch)
Small WL, ^F, ^Amp, ^P
Crest
The highest point on a wave
Amount of decibels cause ear damage
over 130 decibels
Loud sounds do what to your ears. Can it damage it?
Vibrate the tympanic membrane(ear drum) and cochlea.
Yes, rupture ear drum and destroy cells in cochlea.
Thunderstorm outside and temp 30*C. Lightning flash and hear thunder 3.5 sec later. How far away was lightning strike. Round to 2 decimal points.
v=331.5 + 0.6(30)
V= 349.5 m/sec
D= 349.5 m/sec x 3.5 sec
D=1223.25 m
What is oscillation of a wave?
up and down movement of wave
Trough
The lowest point on a wave