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Old March 10th 07, 08:59 PM posted to rec.radio.amateur.antenna
Dave Dave is offline
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First recorded activity by RadioBanter: Jul 2006
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Default Gaussian statics law


"John E. Davis" wrote in message
...
On Sat, 10 Mar 2007 18:38:08 GMT, Dave
wrote:
Gauss's law in Jackson's 'Classical Electrodynamics' 2nd edition, ppg
30-32,33 has NO 't'. nor does it in Ramo-Whinnery-VanDuzer 'Fields and
Waves in Communications Electronics' ppg 70-72(differential form),
75-76(integral form)


This is not surprising since that chapter in Jackson deals with
electrostatics. Look at section 1.5 on page 17. The section states:

The Maxwell equations are differential equations applying locally
at each point in space-time (x,t). By means of the divergence
theorem and Stoke's theorem they can be cast in integral form. [...
a few sentences later...] Then the divergence theorem applied to
the first and last [Maxwell] equations yields the integral
statements... The first is just Gauss's law...

--John


yes, referring to all 4 Maxwell equations you do have a 't' dependency.
however, even equations 1.13 and 1.14 referred to by your quote have NO time
dependency in them. the equations on the next page,1.15 and 1.16 have the
time dependency that the 't' in your quote refers to. remember, those
integrals are NOT integrals over time, they are over the surface or volume.