Dropping the signal frequency below resonance in a parallel LC network results in________________?
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Answer: A. XL decreases and XC increases
Explanation
Dropping the signal frequency below resonance decreases the inductive reactance in the parallel network. Lowering the frequency simultaneously raises the capacitive reactance according to standard reactance equations. The frequency reduction directly alters individual component reactances while maintaining the circuit configuration. Inductive reactance is directly proportional to operating frequency in alternating current electrical circuits. Capacitive reactance is inversely proportional to operating frequency in standard reactive electrical networks. Resonant frequency occurs where inductive and capacitive reactances exactly balance each other out.
Filter design relies heavily on manipulating signal frequencies around resonance to select specific bands. Understanding reactance changes helps engineers troubleshoot tuning issues in communication receiver circuits. Impedance variations near resonance dictate power transfer efficiency in radio frequency systems. Option B incorrectly claims inductive reactance increases while capacitive reactance decreases below resonance. Option C is wrong because line current does not automatically reach a minimum away from resonance. Option D is incorrect since option A correctly identifies the specific reactance changes occurring.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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