Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Contradiction on electric field ?

  1. Oct 6, 2009 #1
    Hello, I'm have just started on this subject, and I am confused with the following equation:

    since E(t) = kq(t)

    => [tex]\frac{dE}{dt}[/tex] = k [tex]\frac{dq}{dt}[/tex] = k*I

    => E = [tex]\int(kIdt)[/tex]

    so if there is a constant current, wouldn't my electric field blow up??

    Thanks!
     
  2. jcsd
  3. Oct 6, 2009 #2

    Dale

    Staff: Mentor

    Hi amrice, welcome to PF
    What is this equation? I have never seen it before.
     
  4. Oct 7, 2009 #3
    Hmmm, it seems that you have defined current improperly. The situation you described is if you had a point charge somewhere in space at t=0, you'd have some electric field from that point charge. Your dq/dt is equivalent to somehow magically increasing the charge of that point charge, which is unphysical and not current. But yes, if you could magically increase the charge indefinitely, the electric field would blow up at t=infinity.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook