The diagram above illustrates an a.c.source of 50V(r.m.s....
The diagram above illustrates an a.c.source of 50V(r.m.s.), 100πHz connected in series with an inductor of inductance L and a resistor of resistance R. The current in the circuit is 2A and the p.d across L and R are 30V and 40V respectively. Calculate the power factor of the circuit
1.33
1.25
0.80
0.75
0.60
Correct answer is C
cosθ=RZ
R = VI=402=20
Z² = R² + XL² = 20² + 15² = √625 = 25
cos θ=RZ=2025=0.8
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