Self-Inductance of a Solenoid (L = μ₀n²Al)

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L = μ₀n²Al

What each symbol means

SymbolWhat it stands for
ACross-sectional area (m²)
LSelf-inductance (H)
lLength of solenoid (m)
nTurns per unit length (1/m)
μ₀Permeability of free space (4π×10⁻⁷ H/m)

When to use this

Long solenoid (l >> radius). Also L = μ₀N²A/l where N = total turns, n = N/l. With core: L = μ₀μᵣn²Al. Energy stored = ½LI². EMF = -L(dI/dt).