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Easy Java Simulations (2001- ) => Collaborative Community of EJS => Topic started by: lookang on September 12, 2012, 04:20:57 pm



Title: Ejs Open Source Magnetic Dipole Field Vector & Field Lines 3D Model Java Applet
Post by: lookang on September 12, 2012, 04:20:57 pm
Ejs Open Source Magnetic Dipole Field Vector & Field Lines 3D Model Java Applet by Wolfgang Christian
original version from http://www.compadre.org/osp/items/detail.cfm?ID=12361
this version is slightly edited by lookang.

work in progress

[ejsapplet]


Magnetic Dipole Field in 3D by Wolfgang Christian
The Magnetic Dipole Field Model displays the field lines and field vectors of a dipole located at the origin and oriented along the z-axis.
 
B = (mu0*m/4*PI)(1/r^3)[3*m cap* r cap)r cp - m cap]




In Cartesian coordinates, the position vector r is ix+jy+kz and the magnetic dipole moment m vector is km.  Perform the dot product gives the following magnetic vector components:
  
Bx = (mu0*m/4*PI) (3*z*x)/r^5
By = (mu0*m/4*PI) (3*z*y)/r^5
Bz = (mu0*m/4*PI)(1/r^3)[ (3*z^2)/r^2-1]


Drag the yellow handle in the 3D view {added slider and inputs field now by lookang for better control] to compute the B field passing through a point (x,y,z).  Select the field option to show the field vectors in plane that passes through the dipole.
Credits:
The Magnetic Dipole Field Model was developed by Wolfgang Christian using the Easy Java Simulations (EJS) modeling tool version 4.3.  You can examine and modify the model for this simulation if you have Ejs installed by right-clicking within the program and selecting "Open Ejs Model" from the pop-up menu.
 
Information about EJS is available at: and in the OSP ComPADRE collection . http://www.compadre.org/osp/items/detail.cfm?ID=12361


Title: Re: Ejs Open Source Magnetic Dipole Field Vector & Field Lines 3D Model Java Applet
Post by: lookang on September 12, 2012, 04:32:56 pm
changes:

added the slider x, y , z for finer control of the field lines to do.
color and arrangement to my usual formal
made field vectors a little more uniformly size
magnet color north=RED and south=BLUE
strangely the author was mike, changed it to Wolfgang Christian, slightly edited by lookang
title Ejs Open Source Magnetic Dipole Field Vector & Field Lines 3D Model Java Applet


Title: Re: Ejs Open Source Magnetic Dipole Field Vector & Field Lines 3D Model Java Applet
Post by: lookang on December 13, 2012, 10:03:40 am
changes a little bit more.

made the point visible on drag, release then draw field lines
made field on drag draw instead of on release


going to make it draw an array of points soonest with engrg1.