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A parallel plate capacitor of capacitance 1 μ F is charged to a potential difference of 20 V. The distance between plates is 1 μ m. The energy density between plates of capacitor is :

1. 1.8 × 10 3 J/m 3
2. 2 × 10 –4 J/m 3
3. 2 × 10 2 J/m 3
4. 1.8 × 10 5 J/m 3

Correct answer: 1.8 × 10 3 J/m 3

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