Question

The temperature dependence of resisatnces of Cu and undoped Si in the temperature range 300-400K, is best described by

(1) Linear increase for Cu, exponential increase for Si

(2) Linear increase for Cu, exponential decrease for Si

(3) Linear decrease for Cu, linear decrease for Si

(4) Linear increase for Cu, linear increase for Si

Answer 1

(2) Linear increase for Cu, exponential decrease for Si

For conductors 

Resistance increases linearly (for not to large increase in temperature) with temperature. 

For semi-conductors 

Resistance decreases non-linearly is an (almost) exponential way