Question

A silver wire has a resistance of 2.1 Ω at 27.5 °C, and a resistance of 2.7 Ω at 100 °C. Determine the temperature coefficient of resistivity of silver.

Answer 1

Temperature, \(T_1 = 27.5 °C\)
Resistance of the silver wire at \( T_1, R_1 = 2.1 Ω \)
Temperature, \(T_2 = 100°C\)
Resistance of the silver wire at \(T_2, R_2 = 2.7 Ω\)
Temperature coefficient of silver = α 
It is related with temperature and resistance as
\(α = \frac{R_2-R_1}{R_1(T_2-T_1)}\)
\(α = \frac{2.7-2.1}{2.1(100-27.5)}\)
\(α = 0.0039 °C^{-1}\)
Therefore, the temperature coefficient of silver is \(0.0039 °C^{−1}.\)