I'd like to know what the energy stored in the magnetic field created by a moving point charge is, as a function of speed. Hopefully, someone knows a relationship like this? or how to get this? I've got a straightforward approach below, but dont know how to integrate it.(adsbygoogle = window.adsbygoogle || []).push({});

BfieldEnergy = f(|v|)

For low constant speeds, not worried about direction, so just the magnitude of v... not worried about relativistic effects either, and lets assume its not accelerating.

My best guess is use u=B^2/2mu0, where B is given by (mu0/4pi)*e(vXr(hat) )/r^2, and integrate that from r = 0 to infinity... but I don't know how to handle the r=0, the integral just explodes... there must be some limit or something. Anyways, I'm guessing the relationship is proportional to |v|^2, but if you know or can figure it out I'd really appreciate it.

thanks

austin

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# Energy in the Magnetic field of a moving point charge, simple question!

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