Cylindrical Capacitor (C = 2πε₀L/ln(b/a))
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C = 2πε₀L/ln(b/a)
What each symbol means
| Symbol | What it stands for |
|---|---|
| C | Capacitance (F) |
| L | Length of cylinder (m) |
| a | Inner radius (m) |
| b | Outer radius (m) |
| ε₀ | Permittivity of free space = 8.85×10⁻¹² F/m |
When to use this
Coaxial cylinders, L >> b so fringing negligible. C ∝ L (capacitance per unit length = 2πε₀/ln(b/a)). Used in coaxial cables.