Easy Electrodynamics Question on Field Lines

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SUMMARY

The electric field is always perpendicular to conducting surfaces in static situations due to the nature of charge distribution on conductors. This principle holds true even for changing electric fields, as the charges within the conductor will adjust to maintain this perpendicularity. Regarding magnetic fields, they do not have sources or sinks, and their lines can only form closed loops. At the surface of a conductor, magnetic field lines are tangential, but they remain perpendicular to the electric field lines due to the div-free condition of the magnetic field.

PREREQUISITES
  • Understanding of static electric fields and charge distribution
  • Familiarity with Gauss's law for magnetism
  • Knowledge of electric and magnetic field line behavior
  • Proficiency in applying the right-hand rule for vector fields
NEXT STEPS
  • Research the behavior of electric fields in dynamic situations using Maxwell's equations
  • Study the implications of the div-free condition of magnetic fields in electromagnetic theory
  • Explore the relationship between electric and magnetic fields in electromagnetic waves
  • Learn about equipotential surfaces and their relationship with electric field lines
USEFUL FOR

Students of physics, particularly those studying electromagnetism, electrical engineers, and educators seeking to clarify concepts related to electric and magnetic fields at conductor surfaces.

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Homework Statement




Explain why the electric field is perpendicular to any conducting surfaces in static situations. Is this true in general (i.e. even for changing electric or magnetic fields)? Are there similar conditions on the direction of a magnetic field at the surface of a conductor.

The Attempt at a Solution



I know how to do the first bit regarding static electric fields, but I can't find anything online about changing electric fields.

Everything I do find says 'Always must be perpendicular', but their justification is that it wouldn't be static if it wasn't normal. Therefore I think it is possible to have non-perpendicular field lines at the surface provided the charges in the conductor aren't static.

I need some sort of justification for this (other than what I've said above) so if you could point me in the right direction it'd be greatly appreciated.

About the magnetic fields, from wikipedia -

"A magnetic field has no sources or sinks (Gauss's law for magnetism), so its field lines have no start or end: they can only form closed loops, or extend to infinity in both directions."​

Now the bit I'm not sure about, is it right to say that these magnetic field lines are perpendicular to the electric field lines near the surface of a conductor? In other words, they look exactly like equipotential lines. Take this (http://hyperphysics.phy-astr.gsu.edu/hbase/electric/imgele/equiv3.gif) image for example, if I were to draw in mag field lines I could trace over the dots and put arrows in a clockwise direction, right?

I'm getting confused because I'm trying to apply the right hand rule and can't think of anything curling around a vector :S

Cheers
 
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The magnetic field B at the surface of conductor is tangential only from the div-free condition of B, (draw a small cylinder across the surface and knowing B=0 inside the conductor tells you vertical B=0). Because they are div-free, their field line at the surface are closed loops. But there are no other restrictions on it. (They are of course perpendicular to E field, because E field is perpendicular to the surface)
 

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