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!

Enduced emf in a loop

  1. May 16, 2013 #1
    1. The problem statement, all variables and given/known data
    A small loop with area 6.8 mm^2 is placed in a long solenoid with 854 turns/cm and a sinusoidally varying current w/ amplitude 1.28 A and angular frequency of 212 rad/s. What is the amplitude of the emf induced in the loop?

    2. Relevant equations
    [itex]\textbf{B}=\mu_0 in[/itex]
    [itex]\Phi_B = BA[/itex]
    [itex]emf = \frac{d\Phi_B}{dt}[/itex]

    3. The attempt at a solution
    Since the current is changing, the emf through the loop should be [itex]\mu_0 n A \frac{di}{dt}[/itex]
    If the angular frequency is 212 rad/s, then the current changes by 1.28 A in half a period, which is [itex]\frac{\pi}{212}[/itex] seconds. So the induced emf should be 6.29E-5 V, but the answer is .198 mV.
     
  2. jcsd
  3. May 16, 2013 #2

    rude man

    User Avatar
    Homework Helper
    Gold Member


    Does not make sense to me.

    If the current is i*sin(wt), what is di/dt? The rest of what you did looks OK.

    BTW I also get 0.198 mV.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted



Similar Discussions: Enduced emf in a loop
  1. EMF induced in loop (Replies: 2)

  2. Induced emf in a loop (Replies: 4)

Loading...