Practice question
Question
Three charges \( +10 \, \mu\text{C} \), \( -7 \, \mu\text{C} \), and \( +5 \, \mu\text{C} \) are at \(
(0, 0, 0) \), \( (10, 0, 0) \), and \( (0, 10, 0) \, \text{m} \). What is the potential at \( (10, 10,
0) \, \text{m} \)? (Take \( \frac{1}{4 \pi \varepsilon_0} = 9 \times 10^9 \, \text{Nm}^2 \text{C}^{-2}
\)).
Explanation
**Electrostatic shielding** inside hollow conducting shell field zero when no charges inside, regardless of external field, because free charges redistribute on outer surface to cancel external field inside conductor, E=0 inside material in equilibrium, consequence of Gauss's law and conductor property. Distances: r₁ = √(10² + 10²) = 10√(2) m , r₂ = 10 m , r₃ = 10 m . V = 9 × 10⁹ ( (10 × 10⁻⁶/10√(2)) + (-7 × 10⁻⁶/10) + (5 × 10⁻⁶/10) ) . V = 9 × 10⁹ ( (10 × 10⁻⁶/14.142) - (7 × 10⁻⁶/10) + (5 × 10⁻⁶/10) ) . V = 9 × 10⁹ (
Discussion
Comments
Please log in to join the discussion.
Login to commentNo comments yet. Be the first to start the discussion.