1. Not finding help here? Sign up for a free 30min 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!

Visualization of a wire & magnetic field

  1. Apr 19, 2004 #1
    Hi,

    I'm having trouble visualizing the way to calculate magnetic flux inside a wire and I was hoping someone here could help me.

    [tex]\Phi_B = \oint B \cdot dA[/tex]

    Inside a wire, using ampere's law, I got:

    [tex] B = \frac{\mu_0 i}{2\pi}\frac{r}{R^2} [/tex]

    And that's where I get stuck. Drawing a diagram of the wire, it seems that B is perpendicular to dA everywhere.

    In the book's solution, they had this perspective of the wire:

    Diagram here And it suddenly makes sense.

    I was just wondering if someone could point out to me how the two diagrams relate? I'm having trouble going from one perspective to the next.
     
  2. jcsd
  3. Apr 19, 2004 #2
    AngelofMusics said: "I'm having trouble visualizing the way to calculate magnetic flux inside a wire...."

    You don't really calculate flux "in" something; you calculate flux through a surface. The magnetic flux through the surface of a cylindrical current carrying wire is zero. But I'm not sure why you want to know this.
     
  4. Apr 20, 2004 #3
    I should have been more clear. I'm calculating the magnetic flux through a wire in a set up where there are two wires parallel to each other. The solution manual says:

    A question, though: Under what circumstances is the magnetic flux through a wire zero? It seems from the book's explanation that it shouldn't be zero at all.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Visualization of a wire & magnetic field
Loading...