Magnetic field induced by a charging infinite plane

AI Thread Summary
The discussion centers on calculating the magnetic field induced by a charging infinite plane using the Ampere-Maxwell law, noting that the magnetic field increases linearly with distance from the center of capacitor plates. When considering infinite plates, the magnetic field's behavior becomes complex, particularly as surface charge density increases at a constant rate. The concept of superluminal electromagnetic waves is mentioned, linking it to phenomena like lightning and pulsars, while emphasizing the magnetic field's direction as circular. Additionally, the intensity of the magnetic field is suggested to follow a hyperbolic curve, approaching an asymptote due to the infinite nature of the plane. Overall, the conversation explores the intricate relationships between electric and magnetic fields in theoretical scenarios.
ItachiUchiha
Messages
1
Reaction score
0
It's a routine to calculate the magnetic field between circular capacitor plates by the Ampere-Maxwell law, and it can be shown that the magnetic field increases linearly with the distance from the center of the capacitor plates, with direction parallel to the plates.

But what if the radius of the capacitor plates tends to infinite? Or, put it the other way, what is the magnetic field between two opposite charged infinite planes, assuming the surface charge density increases at a constant rate σ per second?

Or even simpler, as the title asks, what is the magnetic field induced by a charging infinite plane?
 
Physics news on Phys.org
That's a very good question, an infinite plane would have an infinite answer by definition. must keep to the limit of C per relativity. Not sure on what the rules are on speculation of faster than C, however superluminal ES waves are due to the magnetic field being parallel to the electric field. This is a phenomenon in lightning, pulsars and some high energy plasma research.

If you're asking what direction the field polarity is in then it's circular per the Ampere-Maxwell law as the conjugate E&M pairing dictates. There is also I believe a hyperbolic curve of intensity from the center to the edge, but with an infinite plane it would approach an asymptote I think.
 
Thread 'Motional EMF in Faraday disc, co-rotating magnet axial mean flux'
So here is the motional EMF formula. Now I understand the standard Faraday paradox that an axis symmetric field source (like a speaker motor ring magnet) has a magnetic field that is frame invariant under rotation around axis of symmetry. The field is static whether you rotate the magnet or not. So far so good. What puzzles me is this , there is a term average magnetic flux or "azimuthal mean" , this term describes the average magnetic field through the area swept by the rotating Faraday...
Back
Top