试题详情

U<sub>1</sub>=100sin(314t+120°)V,U<sub>2</sub>=50sin(314t-90°)V,则U<sub>1</sub>与U<sub>2</sub>的关系是(  )。

AA-U<sub>1</sub>滞后U<sub>2</sub> 210°

BB-U<sub>1</sub>滞后U<sub>2</sub> 30°

CC-U<sub>1</sub>超前U<sub>2</sub> 210°

DD-U<sub>1</sub>超前U<sub>2</sub> 30°