A .-100;
B .86.6;
C .-50;
D .50。
[单选题]已知:i=100•sin( t+30°)A,t=0时,i等于()A。A .-100B .86.6C .-50D .50
[单选题]已知:i=100•sin(t+150°)A,t=0时,i等于()A。A .100B .86.6C .-50D .50
[单选题]已知:e=100•sin(ωt-60°)V,t=0时,e等于()V。A .100;B .-86.6;C .86.6;D .-50。
[单选题]已知电流i=[10sinωt+3sin(3ωt+30°)]A,当它通过5Ω线性电阻时消耗的功率P为()W。A . 845B . 325C . 545D . 不确定
[单选题]已知i1=30Sin(100πt十I5°),i2=40Sin(100πt十105°),则i1+i2的初相位是()。A . 90°B . 9°C . 68.l°D . 31.9°
[填空题] 已知il=30sin(100πt+15°)A,i2=40sin(100πt+105°)A,则il+i2=()。
[单选题]已知il=30sin(100t+15°),i2=40sin(100t+105°),则i1+i2的初相位是()。A . 90°B . -90°C . 68.1°D . 31.9°
[问答题] 已知一正弦电流i=5sin(ωt+30°),f=50Hz,问在t=0.1s时,电流的瞬时值为多少?
[单选题]u=-100sin(6πt+10°)V超前i=5cos(6πt-15°)A的相位差是()A .25°B .95°C .115°
[单选题]图示正弦交流电路中,已知u=100sin(10t+45°)(V),i1=i=10sin(10t+45°)(A),i2=20sin(10t+135°)(A),元件1、2、3的等效参数值为:()A . R=5ΩL=0.5H,C=0.02FB . L=0.5H,C=0.02F,R=20ΩC . R1=10Ω,R2=10H,C=5FD . R=10Ω,C=0.02F,L=0.5H