The work done in placing a charge of 8μC on a condenser of capacity 100 nF is:
Correct answer: C. 3.2 x 10⁻⁴ J
- A. 16 x 10⁻⁵ J
- B. 32 x 10⁻⁶ J
- C. 3.2 x 10⁻⁴ J
- D. 16 x 10⁻⁴ J
Explanation
The work done to charge a capacitor is equal to the energy stored, U = Q²/(2C). U = (8 × 10⁻⁶ C)² / (2 × 100 × 10⁻⁹ F) = (64 × 10⁻¹²) / (200 × 10⁻⁹) = 0.32 × 10⁻³ J = 3.2 × 10⁻⁴ J.
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