Temperature Coefficient of Resistance (R = R₀(1 + αΔT))

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R = R₀(1 + αΔT)

What each symbol means

SymbolWhat it stands for
RResistance at temperature T (Ω)
αTemperature coefficient of resistance (/°C or /K)
ΔTTemperature change T - T₀ (°C or K)
R₀Resistance at reference temperature T₀ (Ω)

When to use this

α > 0 for metals (R increases with T). α < 0 for semiconductors (R decreases with T). α for Cu ≈ 3.9×10⁻³/°C. Also α = (R-R₀)/(R₀ΔT). Linear approximation valid for small ΔT.