12
votes
1answer
914 views

Equation describing magnetic hysteresis

So when you're looking at B-H curves for ferromagnetic substances, you often see these magnetic hysteresis curves, which occur, I gather, largely because of domain formation which has some reversible ...
2
votes
3answers
408 views

continuity of the electric potential due to a surface charge

The Electric potential due to a charge distribution on a surface is : $\Phi \left ( x \right )=\int \frac{\sigma \left ( {x^{}}' \right )dx{}'}{\left \| x-x{}' \right \|}da$ I want to show that it's ...
2
votes
1answer
187 views

What determine whether the dynamical equations are tensor equations or vector equations?

Newton's 2nd law which is central to Newtonian dynamics, is a vector equation $\sum\textbf{F}_{external}=m\textbf{a}$ Same with Maxwell's equations in the covariant form. On the other hand, ...
3
votes
2answers
273 views

Are gauge choices in electrodynamics really always possible?

If B is magnetic field and E electric Field, B=rotA, E= -gradV+dA/dt.There is Gauge's invariance, for the trasformation A'->A+gradL/dt, V'->V-dL/dt. Now, we can write: -Coulomb Gauge : the choice of a ...