已知i1=14.1sin(628t-50°)A,i2=70.7sin(628t+40°)A,i=i1+i2,求i最大值,有效值,

问题描述:

已知i1=14.1sin(628t-50°)A,i2=70.7sin(628t+40°)A,i=i1+i2,求i最大值,有效值,

i1=10*(2)^(1/2)sin(628t-50°)A,i2=50*(2)^(sin(628t+40°),这两个矢量相差恰好为90度,故i最大值为(200+5000)^(1/2)=72.11A,有效值为72.11/(2)^(1/2)=50.998A200,5000怎么来的?