##  [Poynting Theorem](/poynting-theorem) 

  ##  [Poynting Theorem](https://engineering.quantumdictionary.io/poynting-theorem-0) 

  

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**Engineering & Applied Technologies Dictionary**

 







 

 

 

 



 

 

 

 

Definition

A local statement of electromagnetic energy conservation that relates the rate of change of electromagnetic energy density u and the divergence of the Poynting vector S = E × H to the power density delivered to charges: ∂u/∂t + ∇·S = −J·E, where u is the field energy density and J·E is the work per unit volume done on charges.