How to solve for power in a piano wire wave problem?

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Homework Help Overview

The discussion revolves around a problem involving a piano wire where a wave travels along it, and the goal is to calculate the average power carried by the wave. The parameters include the mass, length, tension, frequency, and amplitude of the wave.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • The original poster attempts to apply a specific formula for power but expresses confusion over unit conversions and the correct application of parameters. Other participants inquire about the specific question and the attempts made, while one shares their experience with a similar problem, emphasizing the importance of unit consistency.

Discussion Status

The discussion is ongoing, with participants exploring different interpretations of the problem and sharing insights about unit conversions. Some guidance has been offered regarding the need to convert units, but no consensus or definitive solution has emerged yet.

Contextual Notes

There is mention of an online homework program that may impose specific formatting or unit requirements, which could affect how participants approach the problem. The original poster has expressed frustration over multiple attempts to solve the problem correctly.

DGalt
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Homework Statement


A piano wire with mass 3.25 g and length 84.0 cm is stretched with a tension of 27.0 N. A wave with frequency 100 Hz and amplitude 1.30 mm travels along the wire.


Homework Equations


The only equation that I think applies to this one is P = .5*Sqrt(μ*F)*(omega^2)*A^2


The Attempt at a Solution


I've tried this freaking problem five times now, and I'm down to my last try on Mastering Physics (online homework program).
I thought this was a pretty straightforward problem. I started out solving for μ by basically converting the mass (3.25g) to kg and the length (84cm) to m and then dividing the mass by the length. I solved for omega with the equation omega = frequency * 2PI. F I'm assuming is the tension.

Then I thought it was simply a plug-in problem, but I can't seem to get it right. I had to do five different trials because at first I solved for μ wrong and then I wasn't sure what units the program wanted it in (just had Watts next to the solution, so I just assumed i needed to put everything into kg and m and all that stuff). But yea, I don't know what I'm doing wrong.

If anyone can help me out on this one I'd appreciate it, just can't seem to figure out what went wrong

thanks in advance
 
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What's the question?
 
woops...yea I'm an idiot
The question is:
Calculate the average power carried by the wave.
 
what answers have you tried
 
i have the exact same question on my Mastering Physics homework, and I just figured it out. You use that equation and just plug everything in, but the units must be converted for almost everything. So the mass must be in kg, length must be in meters, tension is in N already, frequency is in Hz already, but amplitude must be in meters (not mm). Once you convert everything and plug it into the equation, you get the right answer (mine was about 0.3 W, my numbers may be different than yours though!) For the part B, you just do (1/2) of the amplitude when plugging it in!

Good luck!
 
Clarification? what did you change the formula into?
 

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