1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

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! :)

    Thanks
     
  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! :)
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook