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 $0.0039 °C^{−1}.$