Power required to generate waves

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The discussion centers on calculating the power required to generate transverse waves on a string under specific conditions. The speed of the waves is determined to be approximately 161.19 m/s based on the tension and mass of the string. Participants discuss the formulas for energy and power, emphasizing the relationship between frequency, amplitude, and wave properties. One user successfully calculates the power as 14.72 kW but seeks clarification on finding the angular frequency (omega). The conversation highlights the importance of understanding wave mechanics and the relevant equations to solve such problems.
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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
Answer= 161.1925893 m/s

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
 
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P = ΔE / Δt

From your Energy equation.

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?
 
Thanks, that worked. It ended up being 14.72 kW
 
Hey I have a problem similar to this one. What is the value for the lowercase omega (w)?
I looked everywhere but I don't know how to find it
 
Thread 'Variable mass system : water sprayed into a moving container'
Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
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