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!

Flux through loop around solenoid

  1. Apr 30, 2012 #1
    1. The problem statement, all variables and given/known data
    A simple loop of 5 cm radius encompasses the middle turns of a long coil. The coil has 2500-turns,
    is of length 1 m and radius 1 cm, and carries a current of 10 Amps. What is the magnetic flux through the single loop?


    2. Relevant equations
    B=μIN/L with L=1: B=μIN
    flux=∫B.dA

    3. The attempt at a solution

    flux= μIN*A(loop)= 4π*10^-7*10*π*(5*10^-2)^2
    This is not right apparently

    the actual answer uses the area of the solenoid. Why is that? FLux is the B field dotted with perpendicular area, so why is it the solenoid area? That means that flux is independent of the loop's size!
     
  2. jcsd
  3. Apr 30, 2012 #2
    That is correct.
    Flux DENSITY = B = Webers/m^2
    Flux is in Webers = B x A.
    The solenoid is what is producing the flux and it is constant = B x Area of solenoid
     
  4. Apr 30, 2012 #3
    But I'm looking for the flux through the loop!
     
  5. Apr 30, 2012 #4

    tiny-tim

    User Avatar
    Science Advisor
    Homework Helper

    truesearch :smile: is right …

    there's no magnetic field (and no flux) outside the solenoid :wink:
     
  6. Apr 30, 2012 #5
    But the question asks if there is a magnetic flux through the loop which is outside the solenoid!
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Flux through loop around solenoid
Loading...