一阶测试系统中,在wτ =1处,输出与输入幅值比降为0.707 ,相位滞后_____。A、30度B、60度C、90度D、45度 - 查题网

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一阶测试系统中,在wτ =1处,输出与输入幅值比降为0.707 ,相位滞后_____。
A、30度
B、60度
C、90度
D、45度

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机械工程测试技术

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