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In an L-C oscillating circuit, the maximum potential difference across the inductor is 16 V and the maximum energy stored is 640 microJ. Find the capacitance (in microF) in the circuit.

1. 5
2. 4
3. 3
4. 2

Correct answer: 5

Solution

The total (maximum) energy equals (1/2)C*Vmax² with Vmax = 16 V. Solving gives C = 5 microF.

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