Answer / ran145

In an AC circuit whose impedance consists of reactance as
well as resistance, the voltage and current are not in phase.
when there is reactance in an AC circuit, the product Erms
Irms is greater than the true power. The excess is called
reactive power.

In DC impedance is a pure resistance hence the voltage and
current are in phase which produces true power
i.e.P=Erms*Irms . hence there is no reactive power in DC.

Answer / k.prakashchandra

Dc produces a steady magnetic field unlike AC

Answer / sp

in case of dc supply the frequency is zero

Answer / srikanth

active power is VI COSΦ and reactive power is VI SINΦ.In dc circuits v and I will be in phase.that is Φ=0. so COSΦ=1 and SINΦ=0.so no reactive power.

Answer / haydad ahmad

There is no reactive power in dc circuits because reactive power is produce due to phase difference in ac circuits but which is not in dc circuits .In dc circuits V and I lies at straight line so reactive power in dc circuits is zero.

Answer / rohan joshi

In D.C phase angle is zero. hence power factor is 1.
we know that reactive power is Q=VISin(angle), so its zero.

Answer / sethar12

Is the impedance in a DC motor with magnetic field in its
winding pure resistive? Is the current not consumed in this
inductive load?

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