Mach angle
ș = Mach angle
vsound = speed of sound
vobject = speed of object
Mach number
16.10 - Gotchas
You hear sound because air molecules move from the sound’s source to your ears.No. Air molecules oscillate back and forth as a sound wave
passes by, but there need be no net motion of the particles that make up the medium.
The speed of sound can vary significantly depending on the medium it travels through. Yes. The speed of sound varies widely. Sound travels
nearly five times faster through water than through air, for instance, and faster still through solids, including many metals.
The greater the amplitude of a sound wave, the faster the wave moves. No. The speed of a sound wave is dependent solely on the properties
of the medium through which it moves.
A 20 dB sound is twice as intense as a 10 dB sound. No, the decibel measurement system is logarithmic. The 20 dB sound has ten times the
intensity: ten times as many watts per square meter. A typical person perceives it as twice as loud.
The degree of Doppler shift experienced by a listener is independent of how far the listener is from a moving sound source. This is true:
Distance is not a factor in determining the Doppler shift.(^318) Copyright Kinetic Books Co. 2000-2007 Chapter 16