For a parallel a.c. circuit with a supply voltage of 240 V r.m.s. and current 2.5 A r.m.s., the power factor is 0.9. The true power is:
A) 600 W
B) 540 W
C) 262 W
D) 0 W

Question

Quizplus · Accepted Answer

The formula for true power is P = V x I x cos(theta), where V is the voltage, I is the current, and cos(theta) is the power factor. 
Here, V = 240 V and I = 2.5 A, and cos(theta) = 0.9. 
Therefore, P = 240 x 2.5 x 0.9 = 540 W. 
Thus, the answer is B.

For a Parallel A