FCC Exam Question: 6A207
Given a solenoid with a resistance of 5 ohms and 0.34 through the winding when 1108 at 60 Hz isapplied. What is the impedance?
Explanation: The impedance (Z) of an AC circuit is the total opposition to current flow and is calculated using an AC version of Ohm's Law: Z = V / I, where V is the applied voltage and I is the resulting current. In this problem, the applied voltage is typically 110 V (assuming "1108" is a typo for 110 V, a common household voltage). To arrive at the given answer option A, the current through the winding must be 0.3 A (implying "0.34" is a typo for 0.3 A). Using these values: Z = 110 V / 0.3 A Z = 366.66... ohms Rounding this value gives an impedance of approximately 367 ohms. This aligns with option A. The 5 ohms resistance is the resistive component, but the total impedance of a solenoid in an AC circuit also includes inductive reactance, which makes the total impedance much higher than just the DC resistance. Options B, C, and D are incorrect as they do not result from this calculation.
6A51
6A314
6A300
6A588
6A253
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Includes Elements 1, 3, 6, 7R, 8, and 9.