5. ν=λf
Using k=2π/λ and f=ω/2π, we can write the wave
speed in terms of angular frequency of a harmonic
wave
v= λf=(2π/k)(ω/2π)=ω/k
Wave Speed Relationships
k represents the wave number. We can determine the relationship between k
and λ by the fact that waveform repeats over length λ such that:
D(x)=D(x+λ)
And applying this to D(x)=Asin(kx) gives
k= 2π/λ
6. Two waves on identical strings have frequencies in a
ratio of 2:1. If their wave speeds are the same, how do
their wavelengths compare?
a. 2:1
b. 1:2
c. 4:1
d. 1:4
Example: wave speed and wavelength
Source: http://www.physicsclassroom.com/class/waves/Lesson-2/The-Wave-Equation
7. Two waves on identical strings have frequencies in a
ratio of 2:1. If their wave speeds are the same, how do
their wavelengths compare?
a. 2:1
b. 1:2
c. 4:1
d. 1:4
Example: wave speed and wavelength
Source: http://www.physicsclassroom.com/class/waves/Lesson-2/The-Wave-Equation
Frequency and wavelength are inversely
proportional to each other. The wave with the
greatest frequency has the shortest
wavelength. Twice the frequency means one-
half the wavelength. For this reason, the
wavelength ratio is the inverse of the frequency
ratio.