电工电子技术 2模块二 单相正弦交流电 习题答案.docx

模块二

填空题

2-1u=310sin(314t+π/6)V

2-28A314弧度／秒0.02秒50HZ-π/3

2-3i=310sin(314t+20°)Au=100sin(314t+70°)V50°u50°

2-4380V

2-58sin(314t-π/3)A

2-6相同滞后超前

单项选择题

2-7B

2-8B

2-9C

2-10B

2-11B

2-12A

2-13C

2-14A

综合题

2-15最大值Um=V频率f==50Hz初相=45°

2-16初相位-π/6相位314t-π/6

2-17(1)

(2)

相量图

2-18u1+u2=220sin(314t+30°)

相量图

2-1927.5A6050W

2-20i=7sin(314t-30°)AQ=1540vari=3.5sin(628t-30°)A

2-21I=0.49Ai=0.49sin(314t+120°)AI=0.98A

2-22i=8sin(314t+110°)AP=512WQ=-616WS=801VA