I=U1/R1=55.4/32=1.73A 方法二、 (1) U2=U+U-2U,U2cos(180°-02) =U2+U2+2U,U,cos02 .02=64.9° (2) U =U2 sin0,72.46V UL=41.882 XL-I L=X2/(2πf)=0.133H 02 (3) UR=U2c0s0=33.92V R=0R=19.6Q n R1 R2 L2 + _ U1  U U2  + _ + _ x I ᯩ⌅Ҽǃ U1  U U2  UL  I  R2 U T 2 22 1 2 12 2 2 2 1 2 12 2 2 2 cos(180 ) 2 cos o 64.9 U U U UU U U UU T T T    ? $ I U1 / R1 55.4 / 32 1.73A 2 LX f /(2 ) 0.133 S H 2 sin 72.46 U U L T 2 V 41.88: I U X L L UR U2 cosT 33.92V 19.6: I U R R (1) (2) (3)