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'Current lags voltage' means that in the AC cycle the voltage peaks and the current peaks a little time (a fraction of a cycle) later. This happens with electrical loads like motors.

When the current lags, there is a small period in each half-cycle when the voltage has reversed and the current has not reversed yet. This causes power to flow back into the supply from the load. So there is a loss of average power fed to the load for a given voltage and current.

In this situation the power is the voltage times the current times the power factor, and the power factor is the cosine of the angle by which the current lags the voltage (counting 360 degrees as a full cycle).

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What is the relationship between voltage and current in an inductive circuit?

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What is the bahaviorS of the INDUCTOR in ac supply?

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What is the relationship between the current and voltage in a pure inductive circuit?

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Why current lead voltage in coil?

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What is the relationship between voltage and current in a pure inductive?

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