單項選擇題

已知正弦電磁場的電場強度矢量E(r,t)=E0[excos(ωt-βy)-exsin(ωt-βy)]則電場強度復(fù)矢量(即相量)為()

A.E=-E0(ex-jez)e-jβy
B.E=E0(ex+jez)e-jβy
C.E=E0(ex-jez)e-jβy

微信掃碼免費搜題