# Power required to generate waves

1. Mar 2, 2009

### gleeson.tim

1.
Determine the speed of transverse waves on
a string under a tension of 73 N if the string
has a length of 2.1 m and a mass of 5.9 g

I have a problem with the second part of the question:
Calculate the power required to generate
these waves if they have a wavelength of 29 cm
and an amplitude of 7.3 cm. Answer in units
of kW.

2. Velocity= Square Root [Tension/(mass/length)]

Energy= 2 pi^2 mf^2 A^2
A-amplitude
m-mass
f- frequency

Power= Energy/time

3. I found the frequency by taking the velocity/wavelength and then found the energy using the above equation. I tried to find a value for time by taking the inverse of the frequency (period) and then plugging the values into P=E/t, but was not correct

2. Mar 3, 2009

### LowlyPion

P = ΔE / Δt

E = 1/2*μ*λ*ω2A2

μ = .0059/2.1 = .00281

And your t can be found by λ/ν

making it

P = 1/2*μ*ν*ω2A2

What did you calculate?

3. Mar 3, 2009

### gleeson.tim

Thanks, that worked. It ended up being 14.72 kW

4. Sep 12, 2011

### greenorb

Hey I have a problem similar to this one. What is the value for the lowercase omega (w)?
I looked everywhere but I dont know how to find it