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!

Self inductance question

  1. Aug 28, 2009 #1
    http://i26.tinypic.com/250tkyh.jpg

    the formula for magnetic field
    is like they show but its not divided by l
    like they did

    i cant see a reason why they present it that way
    ??
     
  2. jcsd
  3. Aug 28, 2009 #2

    gabbagabbahey

    User Avatar
    Homework Helper
    Gold Member

    You mean in the equation for [itex]M[/itex]?

    If so, [itex]M[/itex] is the mutual inductance and by definition,

    [tex]\Phi_{\text{total}}=MI\implies M=\frac{\Phi_{\text{total}}}{I}[/tex]
     
  4. Aug 28, 2009 #3
    no
    i am asking about the previous step
    when they found the magnetic field
    and the expression has l in the denominator

    why??
     
  5. Aug 28, 2009 #4

    gabbagabbahey

    User Avatar
    Homework Helper
    Gold Member

    Sorry, the lower case 'L' in your post looked a lot like an upper case 'i' the first time i read it....

    [tex]\frac{N_b}{l}[/tex] would give you th number of turns per unit length in the solenoid, which is what [itex]n[/itex] represents in the version you are probably used to seeing: [itex]B=\mu_0 n I[/itex].
     
  6. Aug 28, 2009 #5
    thanks :)
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Self inductance question
  1. Self inductance (Replies: 1)

  2. Self Inductance (Replies: 0)

Loading...