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!

Number of turns for a solenoid

  1. Mar 18, 2017 #1
    1. The problem statement, all variables and given/known data
    The magnetic field in the middle of a solenoid of length L= 40cm and area of the cross-section A=12 cm^2 is B = 3 mT. The current through the solenoid is I = 4 A. What is the number of turns in this solenoid?

    2. Relevant equations
    BL=μ0*n*I
    =(4πx10^-7)*n*I

    3. The attempt at a solution
    I have attempted this problem many times trying to use the formula above or similar variations of it with no success. I need to use the area of the cross-section in a specific formula to calculate the number of turns. Is there a formula that I'm missing as it is not in my notes, if not how would I proceed?
     
  2. jcsd
  3. Mar 18, 2017 #2

    gneill

    User Avatar

    Staff: Mentor

    What do you consider to be a non successful attempt? Can you show us one? Are you sure that the solenoid cross sectional area is important in this case?

    By the way, there's no RLC circuit involved here. There's no resistor (R) or capacitor (C) involved. I'll change the thread title to have it describe the actual problem.
     
  4. Mar 18, 2017 #3
    You appear to have all the information you need. I'm not sure where your confusion is without an example of your attempt. The only thing I see is that you included L in your equation (which I assume is the length), which you shouldn't have. If you use Ampere's Law, you'll find that the magnetic field in a solenoid is only dependent on the number of turns per unit length (n) and the current running through them (I). The correct equation would therefore be ##B=\mu_0 n I##.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted



Similar Discussions: Number of turns for a solenoid
  1. Solenoid turns (Replies: 1)

Loading...