COMEDK · Physics · 23. Alternating Current
An LCR series ac circuit is at resonance with 10 V each across \(\mathrm{L}, \mathrm{C}\) and R. If the resistance is halved, the respective voltage across \(\mathrm{R}, \mathrm{C}\) and L are
- A \(5 \mathrm{~V}, 5 \mathrm{~V}, 5 \mathrm{~V}\)
- B \(10 \mathrm{~V}, 5 \mathrm{~V}, 5 \mathrm{~V}\)
- C \(10 \mathrm{~V}, 20 \mathrm{~V}, 20 \mathrm{~V}\)
- D \(5 \mathrm{~V}, 10 \mathrm{~V}, 10 \mathrm{~V}\)
Answer & Solution
Correct Answer
(C) \(10 \mathrm{~V}, 20 \mathrm{~V}, 20 \mathrm{~V}\)
Step-by-step Solution
Detailed explanation
In an LCR series circuit at resonance, the inductive reactance \(X_L\) is equal to the capacitive reactance \(X_C\), and the impedance \(Z\) is equal to the resistance \(R\). Given that the voltage across each component is \(V_R = V_L = V_C = 10 \text{ V}\), the current in the…
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