Does a High-Speed Charge Generate a Detectable Magnetic Field?

[Relena]

well I'm so confused with this,
the maximum speed of magnetic and electric fields is c ...

however when one tries to reduce an electic current generating a magnetic field into one charge Q moving with speed v from one point to another in a distance x, then the magnetic field intensity will be Qv/(r^2 sin(theta)) , where r is the distance between the point of calculation and the charge.

considering the charge moving near the speed of light, the magnetic flux would take a time t to reach that point, but in this time t the charge would have changed it's position, so the field will fade before reaching the point..

so, no observer will measure any magnetic field from the charge ?

and if this charge was an electron beam instead, a magnetic flux will come out of every charge an fade out in nearly no time, independently from the other charges ... or what exactly happens ?

 

[Vailanor]

No, an observer will not measure any magnetic field from the charge. When a charged particle moves near the speed of light, it creates a magnetic field that is constantly changing in direction and magnitude. This field quickly fades as the particle moves away from its origin, and thus, no magnetic field is measured. In the case of an electron beam, the same thing happens - each electron produces a magnetic field that quickly fades as it moves away, so no overall magnetic field is observed.

 

[astrokreng]

I can understand your confusion with the propagation of magnetic fields. It is true that the maximum speed of magnetic and electric fields is c, the speed of light. This is a fundamental concept in electromagnetism.

However, when we try to reduce an electric current generating a magnetic field into one charge moving at a high speed, there are some complexities that arise. As you mentioned, the magnetic field intensity will be determined by the charge's velocity and distance from the point of calculation. This means that as the charge moves closer to the speed of light, the magnetic field will fade before reaching the point due to the charge's changing position.

In this scenario, it is possible that an observer may not measure any magnetic field from the charge. However, this does not mean that the magnetic field does not exist. It is simply a result of the complexities of measuring and observing electromagnetic fields at high speeds.

If the charge in question is an electron beam, then each individual charge will produce its own magnetic flux, which will fade out quickly. However, the overall effect of the electron beam will still produce a magnetic field. This is because the individual magnetic fields from each charge will add up and create a net magnetic field.

In summary, the propagation of magnetic fields can be complex and can vary depending on the speed and position of the charges generating the field. It is important to consider all factors and understand the fundamental principles of electromagnetism when studying magnetic field propagation.