What is Poynting vector: Definition and 102 Discussions

In physics, the Poynting vector represents the directional energy flux (the energy transfer per unit area per unit time) of an electromagnetic field. The SI unit of the Poynting vector is the watt per square metre (W/m2). It is named after its discoverer John Henry Poynting who first derived it in 1884. Oliver Heaviside also discovered it independently in the more general form that recognises the freedom of adding the curl of an arbitrary vector field to the definition. The Poynting vector is used throughout electromagnetics in conjunction with Poynting's theorem, the continuity equation expressing conservation of electromagnetic energy, to calculate the power flow in electric and magnetic fields.

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  1. D

    I How to Measure the Energy of an Electromagnetic Wave?

    We know a way of measuring energy of a electromagnetic wave is the Poynting vector, which is independent of the frequency. But let's say we want to make two different electromagnetic waves, with different wavelengths and so different frequency, but with the same amplitude (so same Poynting...
  2. Dario56

    I Is the Poynting Vector Field the Only Factor in Energy Flow in Circuits?

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  3. O

    I Does gravitational energy travel like electrical energy?

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  4. wykk

    A uniformly charged rotating sphere does not radiate, why not?

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  5. L

    Doubts on Exercise Wording: Energy Density & Poynting Vector

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  6. T

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  7. F

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  8. Dario56

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  9. A

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  10. O

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  11. E

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  12. J

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  13. Kaguro

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  14. P

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  15. D

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  16. F

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  17. N

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  18. G

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  19. A

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  20. N

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  21. W

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  22. S

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  23. D

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  24. P

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  25. mayank pathak

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  26. G

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  27. enginej

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  28. E

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  29. P

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  30. J

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  31. enerieire

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  32. rumborak

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  33. P

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  34. sweet springs

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  35. Jackson Lee

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  36. Twigg

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  37. Twigg

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  38. M

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  39. Narayanan KR

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  40. G

    What is the Poynting "vector" mathematically?

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  41. D

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  42. tommowg

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  43. T

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  44. Wesley Strik

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  45. J

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  46. W

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  47. USeptim

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  48. D

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  49. kmm

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  50. Ahmad Kishki

    What is the significance of the Poynting vector for EM waves?

    i need an interpretation for the poynting vector, and its derivation for EM waves (sinusoidal)
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