For semi conductor to have negative temperature coefficient of resistance implies that
A. their resistance decrease with temperature B. The resistance increase with temperature C. their resistance is constantly changing with temperature D. they have electrons and holes at high temperature
Correct Answer: A
Explanation
Temperature coefficient of resistance is given by
α = Increase in resistance per oC rise in temp.
__resistance at 0oC
And for metals where resistance increase with temperature rise, temperature coefficient of resistance is positive; on the other hand in semi conductors, where resistance decrease with temperature rise, temperature coefficient of resistance is negative.
