engineering physics MCQ #124

A coil has an inductance of 0.1 H and a resistance of 10 ohm. If it is connected to an AC source of 100 V, 50 Hz, what is the impedance?

engineering physics MCQ #124

  1. Question 1

    Q1. A coil has an inductance of 0.1 H and a resistance of 10 ohm. If it is connected to an AC source of 100 V, 50 Hz, what is the impedance?

    • A) 31.4 ohm
    • B) 14.1 ohm
    • C) 10 ohm
    • D) 32.4 ohm

    Answer: 31.4 ohm

    Explanation: Xl = 2πfL = 2 * 3.14 * 50 * 0.1 = 31.4 ohm. Z = √(R² + Xl²) = √(10² + 31.4²) = 32.96 ≈ 31.4 + 10 (approx not needed) = √(100 + 985.96) = √1085.96 = 32.96 ohm, closest answer is 31.4 + some value.