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单选题
The () is a measure of the phase difference between voltage and current and is expected as the cosine of phase angle.
A
power
B
efficiency
C
effective power
D
power factor
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单选题With a purely () load the voltage and current are in phase, giving a power factor of one.A
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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
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