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Torque (τ) = pE = qdE. Calculate the torque when q = 2 × 10⁻⁶ C, d = 3 × 10⁻² m, and E = 2 × 10⁵ N/C.

1. 12 × 10⁻³ N·m
2. 10 × 10⁻³ N·m
3. 8 × 10⁻³ N·m
4. 6 × 10⁻³ N·m

Correct answer: 12 × 10⁻³ N·m

Solution

The torque τ is given by τ = pE, where p = qd. Substituting q = 2 × 10⁻⁶ C, d = 3 × 10⁻² m, and E = 2 × 10⁵ N/C, we get p = (2 × 10⁻⁶) × (3 × 10⁻²) = 6 × 10⁻⁸ C·m. Then, τ = (6 × 10⁻⁸) × (2 × 10⁵) = 12 × 10⁻³ N·m.

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