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Homework Help: What is a formula for ENF that relates I (current) and H (Henry) ?

  1. Apr 1, 2010 #1
    1. The problem statement, all variables and given/known data

    I have this question. If I can get that formula, I will be able to solve it! :)

    Here is the question:

    The current in a 51 mH inductor changes with time as I = b t2 − a t. With a = 20 A/s and b = 7 A/s2, find the magnitude of the induced emf, |E|, at t = 1.2 s. Answer in units of V.

    E = Emf

    2. Relevant equations

    This is what I need to know! :)

    3. The attempt at a solution

    I am guessing that I will have to differentiate the equation. Please help! :)

  2. jcsd
  3. Apr 1, 2010 #2
    The induced emf in a pure inductor is -LdI/dt (L in henry)
    You guessed right!
  4. Apr 1, 2010 #3
    thanks! :) it works! :)
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