The resistance of platinum wire at 0°C is 2 Ω and 6.8 Ω at 80°C. The temperature coefficient of resistance of the platinum wire is:
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The resistance of platinum wire at 0°C is 2 Ω and 6.8 Ω at 80°C. The temperature coefficient of resistance of the platinum wire is:

G1 Physics · Accepted Answer

Step 1: Rₜ = R₀(1+αΔT). Step 2: α = (R₈₀−R₀)/(R₀×80) = (6.8−2)/(2×80) = 4.8/160 = 0.03 °C⁻¹. Step 3: α = 3 × 10⁻² °C⁻¹.