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The laws:

$\nabla \times \bar{E} = \bar{I}_{m} - \frac{\partial \bar{B}}{\partial \bar{t}}$

$\nabla \times \bar{H} = \bar{J}_{f} + \frac{\partial \bar{D}}{\partial \bar{t}}$

so how can I remember with fingers or any other deduction method which is minus and which is plus? Since there is now the nabla, I am a bit lost how the cross product hand-rule work.

The term $\bar{I}_{m} = 0$ if magnetic monopoles do not exist. It is there to show that the formulas are of the same structure, cannot just remember which is minus and which is plus.

[Update]

Is it easier to deduce the laws if I suppose that the circuit moves and not the field?

$\bar{v} \times \bar{E} = \bar{I}_{m} - \frac{\partial \bar{B}}{\partial \bar{t}}$

$\bar{v} \times \bar{H} = \bar{J}_{f} + \frac{\partial \bar{D}}{\partial \bar{t}}$

I am unsure whether the formulae are right so please check it. Could this way result in some easy deduction?

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    ...fou$n$d here some non-trivial formulae [here](htt$p$://en.wikipedi$a$.org/wiki/Del_in_cylindrical_and_spherical_coordinates) which helps to do the calculations, not sure yet whether helps to deduce oddity.2011-05-18

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Dear hhh, first of all, magnetic "monotones" are called "monopoles".

Second, you can't replace $\nabla \times$ by $\vec v\times$ in Maxwell's equations because these two objects don't even have the same units.

Third, you must just remember the signs. The Ampere's law, $\nabla\times H= j$, has the plus sign. It's the oldest law mixing electricity and magnetism, so it has the plus sign. It's about the magnetic fields around electric wires. The corresponding currents and magnetic fields around them are described by the right-hand rule.

You may also remember that in this oldest law - magnetic fields of wires - Maxwell's correction $\partial D/\partial t$ also comes with a plus sign.

It then follows that Faraday's law must have the opposite sign - so there is $-\partial B / \partial t$ on the right hand side for the equation for $\nabla \times E$.

But more generally, it's meaningless for you to incorporate "right hand rules" into the form of Maxwell's equations. Right hand rules are not supposed to help you to remember signs in a written form of the equations - on the paper; the "plus rules" and "minus rules" will do.

Right hand rules are supposed to help you to find the directions of vectors in various situations in the real world where there is no God-given understanding which direction in a given setup is "plus" and which direction is "minus". As some people have mentioned before me, "hands" are only useful to define "rules" when you deal with a physical world, so hands are not useful to write down equations in mathematics.

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    @hhh: the physicist is Richard Feynman2011-05-18