A charge of +2 μC is placed at the center of a square with side length 4 m. The electric flux through one face of the square is:
Correct answer: B. 3.76 × 10⁴ N·m²/C
- A. 2.26 × 10⁵ N·m²/C
- B. 3.76 × 10⁴ N·m²/C
- C. Zero
- D. 1.13 × 10⁵ N·m²/C
Explanation
By Gauss's law, total flux through a closed surface is Φ = q/ ε₀, where q = 2 × 10⁻⁶ C and ε₀ = 8.85 × 10⁻¹² C²/N·m². Total flux = 2 × 10⁻⁶ / 8.85 × 10⁻¹² ≈ 2.26 × 10⁵ N·m²/C. For a cube, flux is equally divided among six faces, so flux through one face = 2.26 × 10⁵ / 6 ≈ 3.76 × 10⁴ N·m²/C.
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