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Real Power formulas: P = V I (In DC circuits) P = VI Cos? (in Single phase AC Circuits) P = v3 VL IL Cos? or (in Three Phase AC Circuits) P = 3 VPh IPh Cos? P = v (S2 – Q2)or P =v (VA2 – VAR2) or Real or True power = v (Apparent Power2– Reactive Power2) or kW = v (kVA2 – kVAR2) Reactive power formulas: Q = V I Sin? Reactive Power=v (Apparent Power2– True power2) VAR =v (VA2 – P2) kVAR = v (kVA2 – kW2) Apparent power formulas: S = V I Apparent Power = v (True power2 + Reactive Power2) kVA = vkW2 + kVAR2