Question 101Electricity & Electronics - QMED
70% to passWhich of the following statements concerning AC circuits is correct?
AThe power factor of a resistive circuit is always zero.
BThe current lags the voltage in a capacitive circuit.
CTrue power in an inductive circuit always equals apparent power.
DInductive reactance varies directly with the source frequency.
AI Explanation
The correct answer is D) Inductive reactance varies directly with the source frequency. This statement is correct because in an inductive circuit, the inductive reactance (XL) is directly proportional to the source frequency (f) and the inductance (L) of the circuit. The formula for inductive reactance is XL = 2πfL, which shows that as the frequency increases, the inductive reactance also increases. The other options are incorrect because: A) The power factor of a resistive circuit is 1, not 0; B) In a capacitive circuit, the current leads the voltage, not lags; and C) In an inductive circuit, the true power is usually less than the apparent power due to the reactive component.
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