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Homework Help: Resistance, Voltage, and current

  1. Jul 21, 2017 #1
    1. The problem statement, all variables and given/known data
    Screen Shot 2017-07-22 at 4.46.56 pm.png

    2. Relevant equations


    3. The attempt at a solution
    I chose A, I understand how the resistance is the gradient, but if it is the gradient and the gradient is constant , shouldn't the resistance stay constant? (But the answer is B)
    Please help~thanks a lot~
     
  2. jcsd
  3. Jul 22, 2017 #2

    haruspex

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    I would have answered D. I can see a case to be made for A, but not for B.
     
  4. Jul 22, 2017 #3

    rude man

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    Resistance cannot be defined for a nonlinear component.
    There is "static resistance" and there is "dynamic resistance" but there is no "resistance".
     
  5. Jul 22, 2017 #4
    Can you please explain a bit more? What does that mean in the context of this question? Thank you!
     
  6. Jul 22, 2017 #5

    rude man

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    It means the question should have specified static or dynamic resistance.
     
  7. Jul 22, 2017 #6

    haruspex

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    V/I is the "static" or "chordal" resistance. If that is meant the answer would be D.
    dV/dI is the "dynamic" or "differential" resistance. If that is meant the answer would be A if we take the right derivative at V0 but B if we take the left derivative.
    In short, silly question.
     
  8. Jul 23, 2017 #7
    Thank you~
     
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