(b)解:KVL:(10)+101-20=0得E3A 则 PR=2R=32×10 10=90>0吸收功率 20V P10=-=-10×3 ①0y=-30W<0产生功率 P20=-V1=-20×3 60W<0产生功率KVL : (-10)+10I -20 = 0 得I=3A 则 产生功率 产生功率 吸收功率 60 0 20 3 30 0 10 3 90 0 3 10 2 0 1 0 2 2 = − = − = − = − = − = − = = = W P V I W P V I W P I R V V R ( b ) 20V + + _ I 10V 10 _ 解: