For a series RLC circuit the power loss at resonance is:
Correct answer: C. I²R
- A. V²/ωL
- B. I²Lω
- C. I²R
- D. V²/ωC
Explanation
In a series RLC circuit at resonance, the inductive and capacitive reactances cancel each other out, leaving only the resistance to determine the impedance. Therefore, the power loss at resonance is purely due to the resistance, and is calculated using the formula I2R. Option A and D involve inductance and capacitance, which are not relevant at resonance. Option B includes inductive reactance, which is not a factor in power loss at resonance.
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