坡印亭定理

Poynting's theorem

theorem in physics, showing the conservation of energy for the electromagnetic field, expressed in the form of a partial differential equation developed by British physicist John Henry Poynting

在电磁学中，坡印亭定理是偏微分方程形式说明电磁场的能量守恒的定理，由英国物理学家约翰·亨利·坡印亭发现。坡印亭定理类似于经典力学中的功-能原理，在数学形式上与连续性方程相似。它把能量密度的时间导数，能量的流动，和电磁场做功的速率联系起来。