wave speed Flashcards
y
displacement (m)
A
amplitude (m)
x
postion (m)
λ
wavelength (m)
f
frequency (hz)
φ
phase(radians)
v=λf
λ/T, T is period
wave speed
c = 3 x 10 to the 8 [m/s]
EM waves
four sound ways in a fluid (water or air) the speed is determined by v=(B/p) to the 1/2
bulk modulus (volumetric)
B is bulk
p is density kilograms per cubic meter
for longitudinal (sound) waves traveling down a thin rod the speed is determined by v=(Y/p) to the 1/2
Young’s modulus (tensile)
Y is young
p is kg per meter cubed
for transerve waves in a solid (earthquake S-waves) the speed is determined by v=(G/p) to the 1/2
shear modulus (shear)
g is shear
p is denstiy kg per metter cubed
What sets λ and Τ for a wave?
These are ultimately determined by the material properties of the medium.
Note that λ and Τ are constant parameters of a given wave just like Α,
even though displacement varies with
x and t
for waves on a string the speed is dtermined by v=)T/yu? to the 1/2
tension
t is tension in strong in newtons