正弦交流电流的频率为50Hz,有效值是1A,初相角90°,其瞬时值表达式为( )。 -题库考试答案搜索网

正弦交流电流的频率为50Hz,有效值是1A,初相角90°,其瞬时值表达式为( )。

单选题

2021-07-17 23:46

A、i(t)=sin(314t+90°)A
B、i(t)=<img src="https://s3.cn-north-1.amazonaws.com.cn/qingshuxuetang/examination/imgUplod/1545373346606656851718cd54637bc650e564e3e84c2.png" alt="上传图片">sin(314t+90°)A
C、i(t)=cos(314t+90°)A
D、i(t)=<img src="https://s3.cn-north-1.amazonaws.com.cn/qingshuxuetang/examination/imgUplod/154537335020681573853cb834925a1e62a903bd103fe.png" alt="上传图片">cos(314t+90°)A

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正确答案

B

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标签：新能源科学与工程专升本电工电子技术Ⅰ 期末考试能源与动力工程电工电子学

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