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Homework Help: Seems like a simple problem

  1. Sep 11, 2005 #1
    well heres the problem: A piano tuner detects that the "middle C" note, which should be 261.6 Hz, is too low by 12.6 Hz. If the original tension was 754 N, what must it be adjsuted to so the note plays the correct frequency?

    however i have no idea where to even start?! i got these formulas but i was never given a 4th value like the density (mu) or the velocity of the note in the wire where to go!

    [tex] v = \sqrt{\frac{T}{\mu}} [/tex]
    [tex] v = \lambda f = \frac{\lambda}{t}[/tex] where t is the period, and T is the tension in the string

    as well as this one.. i think its a porportionalitly question im not sure though please help me even get started

    A string is made of two materials of different mass per unit length, 2.31 g/m on the left and 3.25 g/m on the right, connected together at the center. If the wavelength of the wave on the left segment is 21.7 m, what is the wavelength on the right?
    Last edited: Sep 11, 2005
  2. jcsd
  3. Sep 11, 2005 #2
    I'll take a crack at the first problem...I’ve got a bit of a cold, but I think your right. The first question is a proportionality question. If you know that T1=754N and F1=261.6Hz then perhaps an equality would solve this one, you already know what F2 is, now all you need is to solve for T1.

  4. Sep 11, 2005 #3
    agreed as possibly the last problem is the same, however these problems are typically not like that but ill give it a shot thanks
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