Electromagnetism - Poynting vector

AI Thread Summary
The Poynting vector represents the energy flow from a point in an electromagnetic field, indicating both the magnitude and direction of this energy transfer. It is proportional to the momentum density of the field, meaning they share the same direction. A clarification suggests that the Poynting vector quantifies energy flow per unit time and per unit area at the point of evaluation. Understanding this relationship is crucial for grasping electromagnetic theory. Overall, the discussion emphasizes the importance of accurately interpreting the Poynting vector in electromagnetism.
Kontilera
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Hello!
I' currently reading EM and am in need of a verification that I understood it correctly before proceeding. Just to see if I got this right:

The energy flowing out of a point, p, is described by the Poynting vector of the field at that point. The momentum density of the field is proportional to the Poyinting vector and therefore proportional to (i.e. has the same direction as) the energy flow from that point.

Please comment on this if you feel that I'm missing something or important information easily can be added.

Best Regards and Merry Christmas
Kontilera
 
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The energy flowing out of a point, p, is described by the Poynting vector of the field at that point
You may want to sharpen that as:
"Poynting vector is the amount of energy flowing at the point of its evaluation per unit time and per unit of cross sectional area transverse to its direction."
 
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