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A nice way to remember the "governing" eq.

时间:03-22 整理:3721RD 点击:
bedh ombrho J&D

cheers wafer101

to clarify the above:

alterate Div and Curl (or Rot)
equate "bedh" to "ombrho J&D"

b --> B , o --> 0 so Div B =0

e --> E, m --> - , b --> dB/dt so Curl E = -dB/dt (partial diff)

d --> D, rho --> rho so Div D = rho (volume)

h --> H , J&D --> J+dD/dt .......

got it ? (I wish I had tought of this when I was taking electromagnetics)

the word is easy to remember because it sounds like : Bed man -add the word "drink"- Jack Daniels ..... hombro is a spanish word for man ---all we know it even me that I am not spanish.....

so you can think of: BED MAN drink JACK DANIELS

and remember Maxwell equation, at least for me I will never forget it again......

wafer101

Nice effort. I some how prefer to remember the way they are. Since magnetic monopoles do not exist, div B has to be zero. We have done enough of Gauss law to remember that div D = ρfree. The hard part is the curl equations. We know that by Faraday's law the curl of E is the time rate of change of B and is negative of this by Lenz law. So curl E = - d/dt (B). curl H can be written similarly but we must remember to add the displacement current which is obviously unforgettable since that was Maxwell's greatest contribution. So curl H = J + d/dt(D). Note that d/dt written here is actually the partial derivative wrt time.

I feel that remembering this way will also reinforce the basic concepts underlying these great equations.

Of course we must remember that D=εE and B=μH.

-svarun

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