摘要
从电磁场理论P =-∮∑ S·dσ出发 ,分别导出了由电路理论得出的直流电路流电路的功率关系式 ;表明了在电路功率问题上 ,路的关系式也可以从场方程式导出 。
Based on the electromagnetic field theory =-∮ ∑S·d σ,the power formulac of the direct current circuit and alternating current circuit are derived respectively according to the electrocircuit theory.Refering the electrocircuit power,the electrocircuit formula can be derived from the electromagnetic field equation,and it's a special case of the latter.
