单选题The power factor is a measure of the phase difference between voltage and current and is expressed as the（） of the phase angle.AsineBcosineCtangentDcotangent
单选题
The power factor is a measure of the phase difference between voltage and current and is expressed as the（） of the phase angle.
A
sine
B
cosine
C
tangent
D
cotangent
参考解析
解析：
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