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Linear approximation of a nonlinear component.

  1. Jul 18, 2013 #1
    I am trying to find the effective resistance of the NLR in the attachment (to the first order). It is given that IL = gVL2 + I0. I understand that this is normally achieved via ∂g/∂V at V=V0, but when I do so I get that R should be 1/(2gV0), and not 1/2g as shown in the solution. Could anyone please explain to me what it is I am doing wrong? Ought I to first determine V0 and then substitute it in 1/(2gV0)? But then, for my solution to be the same as that in the attachment, won't V0 have to be 1? I'd sincerely appreciate some guidance.

    Attached Files:

  2. jcsd
  3. Jul 19, 2013 #2


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    Staff: Mentor

    Your equation indicates that the coefficient g has units of amps per volt2
    The reciprocal of this must have units of volt2 per ampere. This is not Ohms, nor Ohms-1.

    Therefore, the text book answer cannot be correct.
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