MCQ
In an ac circuit, the power factor
  • A
    Is zero when the circuit contains an ideal resistance only
  • B
    Is unity when the circuit contains an ideal resistance only
  • C
    $1s$ zero when the circuit contains an ideal inductance only
  • Is unity when the circuit contains an ideal inductance only

Answer

Correct option: D.
Is unity when the circuit contains an ideal inductance only
$X_L=2 \pi v L \Rightarrow L=\frac{X_L}{2 \pi v}=\frac{50}{2 \times 3.14 \times 50}=0.16 \mathrm{H}$

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