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!

Current in an infinite current sheet

  1. Feb 15, 2014 #1
    Suppose we have a infinite current sheet of surface density [itex]\sigma[/itex] and apply Ampere’s law to find the magnetic field. Using a rectangular loop of side lengths L, why would the enclosed current be [itex]I=\sigma L[/itex]? Doesn't this imply the RHS has units of [itex]\frac{Q}{m}[/itex]?

    Shouldn't we be looking at this: [itex]I=\frac{dQ}{dt}=\sigma \frac{dA}{dt}[/itex]?
  2. jcsd
  3. Feb 15, 2014 #2


    Staff: Mentor

    A surface current density has units of A/m in the SI system. Multiplying that by length (units of m) gives current (units of A).
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook