If E field points up, which way does B field point?

AI Thread Summary
In a classical electromagnetic wave, if the electric field points upward and the wave propagates to the right, the magnetic field will point toward the observer. The confusion arises from varying depictions in textbooks, which can lead to misconceptions. The correct orientation can be determined using the right-hand rule, where the Poynting vector indicates the direction of wave propagation. The author concludes that the magnetic field must indeed point toward the observer, dismissing the opposite depiction as a drafting error. Understanding these vector relationships is crucial for clarity in electromagnetic theory.
Usaf Moji
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Ok, dumb question, I know. But it's been bugging me, and I can't find a straight answer anywhere, so here it goes:

In a classical electromagnetic wave, where the electric field points upward, will the magentic field point AT me or AWAY from me?

I've seen textbooks depict them both ways - can it really be both ways, or is it just sloppyness on the part of the drafters?

All responses appreciated.
 
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What is the vector definition of the Poynting vector?
 
berkeman said:
What is the vector definition of the Poynting vector?

Ah, I forgot to mention that I'm imagining the electromagnetic wave propagating to our right-hand side. So, I go E cross B with S pointing in the direction of propagation...to answer my own question, the magnetic field must point AT me...and, yes, the opposite depiction in some textbooks must be a drafting error.

Thank you, Berkeman
 
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