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

I Problem I have with second London equation

  1. May 7, 2017 #1
    Second London Equation, which is supposed to represent the current in a superconductor. (SI units)
    ∇×j=-(ns e2/m) B.
    Lets have a look at a super-conducting wire. The magnetic field is:
    B=μ0Ir/(2πr)
    Where Ir is the current enclosed by the radius r.
    We are talking about the current at some depth, not assuming its infinitely thin.
    The problem is, the second London equation predicts the curl of the current is opposite the magnetic field, which conflicts with the direction of the current initially specified. It would predict a relationship between the magnetic field and current that seems impossible.
     
  2. jcsd
  3. May 12, 2017 #2
    Thanks for the thread! This is an automated courtesy bump. Sorry you aren't generating responses at the moment. Do you have any further information, come to any new conclusions or is it possible to reword the post? The more details the better.
     
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: Problem I have with second London equation
Loading...