Question

Two coils A and B are connected in series across a 240 V, 50 Hz supply. The resistance of A is 5W and the inductance of B is 0.02H. The power consumed is 3 kW and the power factor is 0.75. The impedance of the circuit is-

• A. 0.144 W
• B. 1.44 W
• C. 14.4 W
• D. 144 W

Answer 1

Answer: (C)

14.4 W

Answer 2

P = $\frac { E _ { v } ^ { 2 } \cos \phi } { Z }$ Ž P = 3000 = $\frac { ( 240 ) ^ { 2 } ( 0.75 ) } { Z }$

Ž Z = 14.4 W