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A capacitor with capacitance 5 μ F is charged to 5 μ C. If the plates are pulled apart to reduce the capacitance to 2 μ F, how much work is done?

1. 3.75 × 10 –6 J
2. 6.25 × 10 –6 J
3. 2.55 × 10 –6 J
4. 2.16 × 10 –6 J

Correct answer: 3.75 × 10 –6 J

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