Discussion in 'Wireless & RF Design' started by bhuvanesh, Jun 19, 2014.

1. ### bhuvanesh Thread Starter Member

Aug 10, 2013
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while watching video i have seen this statement "oscillating electric field oscillating magnetic field not electromagnetic wave"i dont understand what he really mean.thank you

2. ### nsaspook AAC Fanatic!

Aug 27, 2009
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What video?

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3. ### dougc314 Member

Dec 20, 2013
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Without getting too mathematical, which I'm not really able to do any how I can say that an "electromagnetic wave" such as a radio signal has two varying fields, an electric field and a magnetic field. They are vectors and their direction vectors are at right angles to each other, and as they are two vectors, form a plane. The direction that the radio wave propagates is out of the plane. The Wikipedia article http://en.wikipedia.org/wiki/Maxwell's_equations on Maxwells equations has a very good animated graphic of the E fields and I fields of an electromagnetic wave.

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4. ### alfacliff Well-Known Member

Dec 13, 2013
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and maxwell also says that you cnat have a varying electric field without a magnetic field, or a varying magnetic field without an electric wave at 90 degrees to it.
one creates the other and both toogether are an electromagnetic wave.

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5. ### nsaspook AAC Fanatic!

Aug 27, 2009
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I think it better to say they simultaneously exist as the properties of a single entity and propagate together as real energy moves across space. Create implies one is caused by the other by a process that requires time (lack or presence of causality), so whenever the magnetic field is changing, so is the electric field, and vice versa is 'closer' to being correct.