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Alternating Current — Physics STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 SciencePhysicsAlternating Current2 Marks
Question
What is wattless current.
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Answer

If there is no power expenditure when current flows in an alternating circuit, then the current in the circuit is called wattless current. This is possible when the value of power coefficient is zero.
i.e., $\Psi=0$ or $\Psi=\pi/2$

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