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Homework Help: Finding inductance

  1. Feb 21, 2010 #1

    Find the inductance L. This is for a lab experiment. For a resistor-inductor series circuit, I have a graph of a triangular input waveform from a generator and the voltage across the inductance, VL, as a function of time. I also have the value of the resistance R.

    3. The attempt at a solution

    Well, given this information, I need to find the value of L. I've looked over the equations which seem most relevant but I can't find a suitable one. What am I overlooking?
  2. jcsd
  3. Feb 21, 2010 #2
    Without knowing how your graph looks or any other specifics of your problem, it's a bit hard for me to help, I don't know about anyone else. Here's what I can tell you:

    You know that

    [tex]V = L \frac{dI}{dt} = L \frac{\Delta I}{\Delta t}[/tex]

    which will give you the voltage drop across the inductor.
  4. Feb 21, 2010 #3
    Yeah that's what we did, we rearranged the equation to be L=RV(dt/dv)