Ch2. Sounds Flashcards
What type of wave is sound?
Mechanical
What must sound travel through?
Medium. Enables molecules to compress (squeeze together) and rarefract aka rarefied (stretch apart)
How does sound travel?
In a straight line.
What type of waves are sound waves?
Longitudinal
What do acoustic propagation properties do?
Effects of the medium upon the sound wave
What are the acoustic variables?
Pressure, density, distance
What are the acoustic parameters?
Period
Frequency
Amplitude
Power
Intensity
Wavelength
Propagation speed
What kind of wave is an acoustic wave?
Longitudinal wave
Explain transverse vs longitudinal waves
Transverse: particles move in a direction perpendicular to how the wave propagates
Longitudinal: particles move in same direction that wave propagates
In phase waves
When peaks and troughs occur at the same time and at the same location
Out of phase waves
Peaks and troughs occur at different times
Interference
When more than once sound beam travels in a medium and arrival at same time and place. Both in phase and out of phase waves may undergo this
ID and define the two types of interference
Constructive: when in phase waves form a single wave of greater amplitude.
Destructive: out of phase waves form a single wave of lesser amplitude. There can be two out of phase waves of equal amplitude and result in complete destructive interference
***can occur at the same time with different frequencies
