Practice question

**Electric field concept** visualizes influence of source charge. Uniform field exerts constant force F = qE, and flux Φ = E·A = E A cosθ links field to area orientation, maximum when field normal to surface. Area vector Δ S = 0.3 × 0.5 = 0.15 m² along z-axis. Flux: Φ = E · Δ S = 2 × 10³ × 0.15 = 300 N·m²/C . Substituting values gives 300 N·m²/C, which matches expected magnitude for this electrostatic configuration, confirming Coulomb's and Gauss's principles and charge quantization consistency.