Notes
• “Normal Week”, except that I will be away starting
t
tomorrow,
so Office
Offi Hours
H
are only
l today
t d
• Normal Help Sessions
• Class continues “as usual”, but with different profs
Energy and Power in Wave Motion
A line source emits a cylindrical expanding wave.
Assuming that the medium through which it travels
absorbs no energy, find how
a) the intensity, and
b) the amplitude
vary with the distance from the source.
Chapter 17: Sound Waves
• Longitudinal Wave
– gas is compressed
– density/pressure
wave propagates in
the gas
Sound as Pressure/Density Wave
Sound as Displacement Wave
Sound Waves
Pressure
dP = 0 (Constant pressure, no net Force)
dx
Direction of Force changes
Displacement
F=0  no motion
Maximal motion
The Speed of Sound
Doppler Shift
Ts is period of
the sound
wave us is
wave,
velocity of the
source
Shock Waves/Sonic Boom
Power of Sound Waves
Intensity of Sound Waves
Range of Hearing