Question

The resistance of metals is often temperature dependent. The dependence is characterized by the Temperature Coefficient of Resistance (TCR), which is related to temperature according to R=Rref[1+TCR*(T-Tref)] over limited temperature range. Rref is the resistance at some temperature Tref. If the TCR of a platinum wire is 0.00393/°C and its resistance is known to be 20.1 Ω at 25°C, what is the temperature of the wire if its resistance is 19.5 Ω?

Answer 1

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