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In an LC oscillator, the capacitor attains a peak charge of Q. What is the capacitor charge when the energy is shared equally by the electric field of the capacitor and the magnetic field of the inductor?
- Q/2
- Q/√3
- Q/√2
- Q
Correct answer: Q/√2
Solution
Total energy = Q^2/(2C). Equal sharing means capacitor energy = Q^2/(4C) = q^2/(2C), giving q^2 = Q^2/2, so q = Q/sqrt(2).
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