Magnetic field of moving charged particle

AI Thread Summary
The discussion focuses on modeling the magnetic field generated by a moving charged point particle, noting that the Biot-Savart law may not apply due to the lack of steady current. When a charged particle passes through a conducting loop, it creates an azimuthal magnetic pulse; however, there is no induced azimuthal EMF because there is no net magnetic flux linking the loop. The magnetic field produced by both point charges and steady currents is azimuthal, while the electric field is radial. For relativistic point charges, the fields' longitudinal extent is reduced, resulting in very short, high-amplitude pulses. This highlights the complexities in calculating induced EMF in such scenarios.
grundletaint
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What is the appropriate way to model the magnetic field of a moving charged point particle?

I don't believe you can use Biot-Savart because it is not a steady current.

I am trying to figure out what EMF (current) would be induced in a square or round conducting loop when a charged point particle passes through it.

Thanks
 
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Maybe BS Equation help, integrating over a single point.

\vec{B}(\vec{r})=\dfrac{\mu_0}{4\pi}\dfrac{e (\vec{v} \times \hat{r})}{r^2}
 
The point charged particle moving through a loop will develop an azimuthal magnetic pulse, but because there is no net magnetic flux linking the loop, there will be no induced azimuthal EMF. The magnetic field from either a point charge-current or a steady current is azimuthal, and the electric field is radial. For relativistic point charges, the longitudinal extent of the fields are collapsed by the factor gamma, so the observed pulses are very short, and very high amplitude.
 
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