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 $\Psi=\pi/2$
i.e., $\Psi=0$ or $\Psi=\pi/2$
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