Results 1 to 4 of 4

Math Help - amperes law question..

  1. #1
    MHF Contributor
    Joined
    Nov 2008
    Posts
    1,401

    amperes law question..

    here is a question:
    http://i25.tinypic.com/fc8rqr.jpg

    there is endless cylinder i which we only see its crossection in the photo.
    its radius is [tex]R_1[] a distance d from the center a cylinder with radius [tex]R_2[]
    along the cylinder flows current I in a uniform way inside the page(X).
    1.what is the magnetic field in x>0 region?
    2.what is the magnetic field in (0, R_1)?

    i tried to solve it by amperes law
    \oint \vec{B}\vec{dl}=\mu_0 I
    0<r<d
    \oint \vec{B}\vec{dl}=\mu_0 I\\
    I_0=I\frac{\pi r^2}{\pi R_1^2}=I\frac{ r^2}{R_1^2}\\
     B =\mu_0 I\frac{ r^2}{R_1^2 2\pi r}\\

    have i done the first region correctly
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor
    Joined
    Nov 2008
    Posts
    1,401
    dl vector is the way we are going
    but we can go clock wise and counter clock wise
    and in each case i will have a different result
    ??
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Flow Master
    mr fantastic's Avatar
    Joined
    Dec 2007
    From
    Zeitgeist
    Posts
    16,948
    Thanks
    5
    Quote Originally Posted by transgalactic View Post
    dl vector is the way we are going
    but we can go clock wise and counter clock wise
    and in each case i will have a different result
    ??
    It might be better to post your physics questions here: http://www.physicshelpforum.com/physics-help/
    Follow Math Help Forum on Facebook and Google+

  4. #4
    MHF Contributor
    Joined
    Nov 2008
    Posts
    1,401
    i have tried posting there before
    nobody answers there at all
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. another amperes law question..
    Posted in the Advanced Applied Math Forum
    Replies: 1
    Last Post: August 25th 2009, 08:51 AM
  2. find Amperes per second
    Posted in the Calculus Forum
    Replies: 2
    Last Post: April 11th 2009, 05:09 PM
  3. Electrical Circuits? - Resistance, ohms, amperes
    Posted in the Advanced Applied Math Forum
    Replies: 3
    Last Post: November 13th 2007, 03:13 AM

Search Tags


/mathhelpforum @mathhelpforum