Term
What type of wave is a sound wave? |
|
Definition
|
|
Term
since a sound wave is a mechanical wave, it must do what? |
|
Definition
|
|
Term
What are the three parts of the sonic spectrum? |
|
Definition
infrasonic, audio portion, ultrasonic |
|
|
Term
What is the range of frequencies that humans can hear? |
|
Definition
|
|
Term
In what type of medium does sound travel the fastest? |
|
Definition
|
|
Term
How do you determine the speed of sound in air? |
|
Definition
|
|
Term
Harmonic content is heard as _____. |
|
Definition
|
|
Term
How do humans perceive intensity? |
|
Definition
|
|
Term
HOw do you calculate the sound or relative intensity of a sound (loudness)? |
|
Definition
|
|
Term
|
Definition
10 to the -12 w/m squared |
|
|
Term
What is the unit of relative intensity? |
|
Definition
|
|
Term
How does the ear hear frequency? |
|
Definition
|
|
Term
How do you calculate the perceived frequency using the doppler equation? |
|
Definition
|
|
Term
What is the doppler effect? |
|
Definition
apparent shift in frequency due to motion between the listener and the source |
|
|
Term
HOw does the pitch change if the listener and source are getting closer together? Farther apart? |
|
Definition
closer-ptich is higher; farther-pitch is lower |
|
|
Term
What term is given to the lowest frequency a vibrating string can produce? |
|
Definition
fundamental frequency (f1) |
|
|
Term
What is the relationship between the length of the string and the wavelength of the fundamental? |
|
Definition
wavelength=2l or length=1/2wavelength |
|
|
Term
|
Definition
whole number multiples of the fundamental frequency |
|
|
Term
What is the relationship between the length of a closed pipe and the wavelength of the fundamental frequency? |
|
Definition
|
|
Term
What harmonics can a closed pipe produce? |
|
Definition
|
|
Term
What is the relationship between the length and wavelength of the fundmanetal for an open pipe? |
|
Definition
|
|
Term
What harmonics can an open pipe produce? |
|
Definition
|
|
Term
What is the quality of sound? |
|
Definition
the number of harmonics present and their relative intensities |
|
|
Term
When do frequencies sound good together? |
|
Definition
when they reduce down to a small whole number ratio, close together numbers (4/5, 1/2, etc.) |
|
|
Term
|
Definition
amplitude pulsations when 2 frequencies are close together |
|
|
Term
If one frequency of 278 hz is played at the same time as 281 hz, how many beats will be heard? |
|
Definition
|
|
Term
What determines the speed of sound in a medium? |
|
Definition
the elasticity and density of the medium |
|
|
Term
|
Definition
the rate of energy flow though a unit area |
|
|
Term
Do we hear all frequncies with equal intensities? |
|
Definition
no, sounds of higher intensity are usually louder but sounds of high frequency may not seem as loud as a sound of low frequency of equal intensity |
|
|
Term
When is a shock wave formed? |
|
Definition
if teh source is moving higher than the wave |
|
|
Term
when is the velocity of the observer zero? |
|
Definition
|
|
Term
When is the velocity of teh observer positive or negative? |
|
Definition
it is positive if the observer moves toward the source and negative if teh observer moves away from the source |
|
|
Term
How does an oscilloscope display a sound wave? |
|
Definition
|
|
Term
_____is when a vibrating object can cause a second object with the same natural frequency to vibrate with a large amplitude. |
|
Definition
|
|
Term
|
Definition
|
|