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Gauss's Law

Electric Flux & Gaussian Surfaces — Calculation, Visualization & Graphs

Φ = ∮ E · dA = Q_enc / ε₀
ε₀ = 8.8541878176 × 10⁻¹² C²/(N·m²)

1. Enter the Values

2. Calculated Result

Net Electric Flux (Φ_E)

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Enter values and click Calculate.

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3. Step-by-Step Solution

Enter values above to generate the complete solution.

4. Solid Angle & Spherical Surface Visualization (Fig 3.4)

5. Gauss's Law Graphs

Flux vs Enclosed Charge (Φ vs Q)

Flux increases linearly with the enclosed charge Q.

Live point: —

Electric Field vs Radius (E vs r)

Electric field obeys the inverse-square law with respect to radius.

Live point: —

6. Important Relationships

Φ ∝ Q_enc

Flux depends entirely on the enclosed charge.

Φ ∡ Shape

Flux is independent of Gaussian surface geometry.

E ∝ 1/r²

Field intensity drops with the square of distance.

Q_ext = 0 Flux

Charges outside the surface yield net zero flux.

7. Theory

What is Gauss's Law?

Gauss's Law states that the net electric flux passing through any closed surface is equal to the net charge enclosed by that surface divided by the vacuum permittivity (ε₀).


Integral Form & Solid Angle

dΩ = (u_r · n̂ ds) / r² = ds' / (r')²

Φ_E = ∮_S E · n̂ ds = Q_enc / ε₀

Where:

Φ_E = total electric flux (N·m²/C or V·m)

E = electric field vector (N/C)

ds = differential area element on arbitrary surface S

ds' = projected differential area element on concentric sphere S' of radius r'

Q_enc = net electric charge inside the surface (C)

ε₀ = 8.854 × 10⁻¹² C²/(N·m²)