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!

Magnetic permeability and magnetic resistance

  1. Jun 10, 2006 #1
    hi from ukraine
    i'm a electronic engineering student at kiev polytechnic university
    i need your helps
    how can i calculate this question
    The steel winding with the number of coils w= 200 is put on thr ring-like closed
    core in regular intervals.The section is rectangular. The external diameter of a ring
    D=16 sm, the interval diameter d=10 sm, thickness b=4 sm.Magnetic induction B in
    the core have to be equal 1 T1. How will current and magnetic resistance changes,
    if the nonmagnetic (air) 'interval b=0.5 mm would be made. Magnetic flux has to be
    constant.Define the relative magnetic permeability and magnetic resistance of the
    ferromagnetic steel and sheet steel 1512 cores, if the magnetic flux in the interval
    (theta)=1.2x1/1000 Wb. Dependence B(H) for steel is approximate to a such data:
    0,2(80)0,4(185)0,6(300)0,8(460)1,0(750)1,2(1500)
    i find three links http://www.classictesla.com/download/indu_pt_1.pdf
    http://www.classictesla.com/download/indu_pt_2.pdf
    http://www.technick.net/public/code/...nce_calculator
    but i couldn't calculate
     
    Last edited: Jun 10, 2006
  2. jcsd
  3. Jun 10, 2006 #2

    Gokul43201

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    kievstar, I don't understand the setup. Do you think you can attach a picture?
     
  4. Jun 12, 2006 #3
    thanks for your interest i'll attach as soon as possible
     
  5. Jun 12, 2006 #4
    i gues one of theese is about with my question
    i say guess because tehre is no given picture with questions
     

    Attached Files:

  6. Jun 12, 2006 #5

    berkeman

    User Avatar

    Staff: Mentor

    Sounds like it's a square cross-section toroidal core, with ID=10cm and OD=16cm, with 300 turns of wire. The question is asking about the change in reluctance when an air gap is introduced. I don't get the part about "Magnetic induction B in the core have to be equal 1 T1." Maybe the attachments will clear that up when they get approved.
     
  7. Jun 13, 2006 #6
  8. Jun 13, 2006 #7
    anyone to help?:cry:
     
  9. Jun 13, 2006 #8

    berkeman

    User Avatar

    Staff: Mentor

    Oh, sorry, from your last post I thought you had it figured out. Please post your work so far, and I'll take a look at it. What part are you having trouble with? What does your textbook say about air gaps?
     
  10. Jun 14, 2006 #9
    don't worry i calculated yesterday:rofl:
    thank's for your interest:smile:
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?