Practice question

**Gauss's law** Φ = ∮ E·dA = q_enc/ε₀ is fundamental relation between flux and enclosed charge. For charge at centre of cube, total flux = q/ε₀ distributes equally over six faces, each receiving Φ/6, but total remains q/ε₀ irrespective of cube edge. Φ = (q/ε₀) . q = Φ ε₀ = 7.91 × 10⁵ × 8.854 × 10⁻¹² = 7 × 10⁻⁶ C = 7 μC . Substituting values gives 7.0 μC, which matches expected magnitude for this electrostatic configuration, confirming Coulomb's and Gauss's principles and charge quantization consistency.