Question

The resistance of a conductor increases with temperature, what type of conductor can it be?

• A. Metallic
• B. Electrolytic
• C. Can be both
• D. Can be none

Answer 1

Answer: (A)

Metallic

Answer 2

For metallic conductors, resistivity (and hence resistance) increases with temperature following:
$\rho = \rho_0 \bigl[1 + \alpha (T - T_0)\bigr]$
where
• $\rho_0$ is resistivity at reference temperature $T_0$
• $\alpha$ is the positive temperature coefficient of resistivity

Electrolytic conductors exhibit a decrease in resistance with rising temperature (negative temperature coefficient) due to enhanced ion mobility.