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I have a question. My personal curiosity only. I love magnets and a have a couple of them. Do you know any cheap or free tools, that work in the browser/osx/l

I have a question. My personal curiosity only. I love magnets and a have a couple of them. Do you know any cheap or free tools, that work in the browser/osx/linux and can simulate how magnets interact? How 2 or 3 magnets interact with each other, how magnetic forces interact etc. It must not be 100% accurate, just ballpark estimation for fun playtime :)

terragon 8y ago
Yes! I would love to help out if someone starts with the basic structure of such a project. I've been searching for something like this for years.
dekhn 8y ago
Why not use a physics engine? Model the magnetism as attractive/repulsive forces.
jamportz 8y ago
The following is a visualization of electric field lines (for a "quadrupole" of charges): https://twitter.com/jamportz/status/1079777103892135936 https://twitter.com/jamportz/status/1079777103892135936 https://tinyurl.com/y859v78t https://tinyurl.com/y859v78t For magnetic fields, the problem is there are no simple (non-trivial) solutions for the magnetic fields of interesting things like a bar magnet. Even the magnetic field of a circular loop of current involves elliptic integrals. (see e.g. https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20010038494.pdf https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/200100...). What you could do is numerically solve the https://en.wikipedia.org/wiki/Biot%E2%80%93Savart_law https://en.wikipedia.org/wiki/Biot%E2%80%93Savart_law (given your currents) inside the GLSL shader.. Though this will probably be very slow..
cr0sh 8y ago
Quickfield has a free "student edition": https://quickfield.com/index.htm https://quickfield.com/index.htm I also recall there being at one time a DOS-based magnetic field simulation software, but I can't recall the name of it. Probably could find it (or at least the shareware version) in a simtel archive somewhere. If you really want a better answer for this, look into browsing and asking around one of the various "magnetic overunity" perpetual motion/energy sites out there. Tons of people out there using such software trying to crack the laws of thermodynamics and extract "free energy" from magnets - here's a start down that wormhole: http://jnaudin.free.fr/ http://jnaudin.free.fr/
jamportz 8y ago
This app is pretty decent: https://www.falstad.com/vector3dm/ https://www.falstad.com/vector3dm/ Looking at the source code, indeed many of the magnetic fields are computed via the Biot-Savart law, though some interesting ones are not. I might try rendering them.

terragon 8y ago

Yes! I would love to help out if someone starts with the basic structure of such a project. I've been searching for something like this for years.

dekhn 8y ago

Why not use a physics engine? Model the magnetism as attractive/repulsive forces.

jamportz 8y ago

The following is a visualization of electric field lines (for a "quadrupole" of charges): https://twitter.com/jamportz/status/1079777103892135936 https://twitter.com/jamportz/status/1079777103892135936 https://tinyurl.com/y859v78t https://tinyurl.com/y859v78t For magnetic fields, the problem is there are no simple (non-trivial) solutions for the magnetic fields of interesting things like a bar magnet. Even the magnetic field of a circular loop of current involves elliptic integrals. (see e.g. https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20010038494.pdf https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/200100...). What you could do is numerically solve the https://en.wikipedia.org/wiki/Biot%E2%80%93Savart_law https://en.wikipedia.org/wiki/Biot%E2%80%93Savart_law (given your currents) inside the GLSL shader.. Though this will probably be very slow..

cr0sh 8y ago

Quickfield has a free "student edition": https://quickfield.com/index.htm https://quickfield.com/index.htm I also recall there being at one time a DOS-based magnetic field simulation software, but I can't recall the name of it. Probably could find it (or at least the shareware version) in a simtel archive somewhere. If you really want a better answer for this, look into browsing and asking around one of the various "magnetic overunity" perpetual motion/energy sites out there. Tons of people out there using such software trying to crack the laws of thermodynamics and extract "free energy" from magnets - here's a start down that wormhole: http://jnaudin.free.fr/ http://jnaudin.free.fr/

jamportz 8y ago

This app is pretty decent: https://www.falstad.com/vector3dm/ https://www.falstad.com/vector3dm/ Looking at the source code, indeed many of the magnetic fields are computed via the Biot-Savart law, though some interesting ones are not. I might try rendering them.