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|Re: Absolute Nothing Does Not Exist
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Posted by Zephram Cochrane/">Zephram Cochrane on February 8, 2000 21:39:29 UTC
: : We do not pretend, but do understand the propagation of electromagnetic waves. Its not a very complicated phenomenon. If you don't that's your problem.
: 0KAY SO YOU KNOW PLEASE ANSWER THIS : WHATS A ELECTROMAGNETIC WAVE 0KAY ? : IF THERE IS A NO MEDIUM (ABSOLUTE NOTHINGNESS IS TERMED USED )TO PROPOGATE THEN HOW DOES IT TRAVEL.
Simple, 1.) ÑXE = -¶B/¶t (Translation, a changing magnetic field creates an electric field in vacuum)
2.) ÑXB = m0e0¶E/¶t (Translation, a changing electric field creates a magnetic field in vacuum)
3.) Ñ×E = 0 (Translation, we have no electric charge sources of the electric field being in vacuum)
4.) Ñ×B = 0 (Translation, no magnetic monopoles)
Take the curl of (1.) 5.) ÑX(ÑXE) = ÑX(-¶B/¶t)
A little manipulation 6.) ÑX(ÑXE) = (-¶/¶t)(ÑXB)
Inserting (2) into (6) 7.) ÑX(ÑXE) = (-¶/¶t)(m0e0¶E/¶t)
A little manipulation 8.) ÑX(ÑXE) =-m0e0¶2E/¶t2
A little vector calculus 9.) Ñ(Ñ×E) - Ñ2E = -m0e0¶2E/¶t2
Refer to (3), then (9) becomes Ñ2E = m0e0¶2E/¶t2
This is a wave equation for an electric wave of speed c = 1/(m0e0)1/2
In other words its because a changing electric field creates a magnetic field and because a changing magnetic field creates an electric field in this manner that the electric field propogates as a wave without a medium. One can use the same kind of method with the same equations 1, 2, 3, 4 to arive at Ñ2B = m0e0¶2B/¶t2
: cHECK OUT YOUR BASICS THEN REPLY.
I have gone far beyond the basics like these things.
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