- 搜標題
- 搜題干
- 搜選項
單項選擇題
若i1=10sin（wt+30°）A，i2=20sin（wt-10°）A，則的相位比超前（）
A.20°
B.-20°
C.40°
D.-40°
A.20°
B.-20°
C.40°
D.-40°
