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Homework Help: Beat FrequencyWhat is the new tension in the string that slipped?

  1. Jan 20, 2010 #1
    Two identical strings are sounding the same fundamental tone of frequency 156 Hz. Each string is under 228 N of tension. The peg holding one string suddenly slips, reducing its tension slightly, and the two tones now create a beat frequency of three beats per second. What is the new tension in the string that slipped?

    My attempt so far:

    fbeat = f1 - f2 = 3Hz

    f1 = 156Hz

    3Hz - 156Hz = -f2

    f2 = 153Hz

    So how do I find the tension for this frequency? Usually there is more information given such as the linear density or speed of the wave. I dont see how I can find the tension without those variables. Any help?
  2. jcsd
  3. Jan 20, 2010 #2


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    Homework Helper

    For identical strings frequency f = k*(T)^1.2, where k is constant and T is the tension in the string. So
    f1/f2 = (T1/T2)^1/2.
    You have already found f1 and f2. T1 is given. Find T2.
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