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 bottle

  1. Apr 29, 2008 #1
    I was wondering about a good application to plot the path of a particle in a magnetic bottle (i.e. the magnetic field in the region between two coaxial circular loops of wire)

    I was thinking that maybe I could use Biot Savert's (sp.) law

    [tex]d\textbf{B} = \frac{\mu_0}{4\pi} \frac{Id\textbf{l} \times \textbf{\hat{r}}}{r^2}[/tex]

    and

    [tex]d\textbf{F} = q\textbf{v} \times d\textbf{B}[/tex]

    but, as I mentioned earlier, I don't have a good application for that. Worse comes the worse, I could try and write a program to do it, but

    1. I don't know what method of approximation to use, and
    2. I'm not very good at coding.
     
  2. jcsd
  3. Apr 29, 2008 #2
    Thats a surprisingly complex situation; you won't be able to plot it analytically unless you take some drastic approximations.
    I suggest... either you find an animation of it online (shouldn't be hard). Or you learn to code and find a numerical solution.
     
  4. Apr 29, 2008 #3
    err... I know how to code, but I can never seem to get my programs to work right. I know java, but I'm not sure if that's the best language to use for this. Any ideas?
     
  5. Apr 30, 2008 #4
    I've used java and C++, and i find java to work well for programming simulations (at least for my purposes). The problem is going to be plotting in 3D. Java 2D works great, but i hear that 3D is pretty rough (though i've never tried it).
     
  6. Apr 30, 2008 #5
    Ok, then, I'll look into java 3d. But what method(s) should I use for approximation?
     
  7. Apr 30, 2008 #6
    Well, make the loops perfectly conducting, with a fixed constant current in each (should be going in the same direction).
    From that you can use the Biot-Savart law to find the magnetic field everywhere--> you'll need to set up the B = integral_____.... then use some method of numerical integration. the fourth order runga-kutta is the standard method for numerical integration, but i'd recommend a simple Euler's method (at least to start with). Once you have the magnetic fields everywhere, you can use the lorentz force equations to find the acceleration --> numerically integrate to find velocity --> and again to find positions as a function of time.
    Does that make sense?
    One simplification to start with, would be to only plot 2 of the 3 dimensions, it would surely give you something cool to look at!
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Magnetic bottle
  1. Magnetic bottle (Replies: 3)

  2. Tip a bottle (Replies: 11)

  3. Experiment with bottle (Replies: 3)

  4. Force on bottles (Replies: 2)

Loading...