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!

Does a straight non-time-dependent E field create a circular B field?

  1. Sep 20, 2011 #1
    I was under the impression that it does, you know from Ampere's law. But today, my professor told me that Electric and Magnetic fields are very similar (although I can't imagine they are exactly the same, since there are no magnetic monopoles), THAT a non-time dependent E field does not create a circular B field. Does this mean that a current in a wire is actually a time-dependent E field?


    PS. the course that this was from was Relativistic Electrodynamics.
  2. jcsd
  3. Sep 20, 2011 #2


    User Avatar
    Science Advisor

    No, in this example there is no E field. It's the current in the wire that creates the B field.
  4. Sep 21, 2011 #3


    User Avatar
    Science Advisor
    Gold Member
    2017 Award

    Nevertheless, relativity tells us that there is not a seperated E and B field, but only one electromagnetic field. If you have in one frame of reference a pure electrostatic E field in another frame of reference, moving relative to the first, you have both an E and a B field. Both fields together make up the electromagnetic field. (E,B) are the components of an antisymmetric 2nd-rank tensor in Minkowski space.
  5. Sep 21, 2011 #4


    User Avatar
    Science Advisor

    That's quite true, but has nothing to do with the present thread. The question was, "is the current in a wire actually a time-dependent E field?" and the answer is no.
  6. Sep 22, 2011 #5
    Actually, there was at some moment an E field (for the current to be there in the first place) but no longer there is, whether one decides to attribute the B field to this E field change or to the actual current it makes no difference at all.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Similar Discussions: Does a straight non-time-dependent E field create a circular B field?
  1. Non-Conservative E-field (Replies: 13)