At a high temperature, the resistance of a thermistor is?

At a high temperature, the resistance of a thermistor is?

• A. Low
• B. High
• C. Medium
• D. Zero

Answer: (A)

Thermistors are temperature-dependent resistors. The common sensing type has a negative temperature coefficient, so resistance decreases as temperature rises. As temperature increases, more charge carriers are thermally activated in the semiconducting material, boosting conductivity and lowering resistance. This means at high temperature the resistance is low. If it were a positive-temperature-coefficient thermistor, the resistance would increase with temperature, which is not the case here. A zero resistance would imply a perfect conductor, which thermistors do not exhibit.

Thermistors are temperature-dependent resistors. The common sensing type has a negative temperature coefficient, so resistance decreases as temperature rises. As temperature increases, more charge carriers are thermally activated in the semiconducting material, boosting conductivity and lowering resistance. This means at high temperature the resistance is low. If it were a positive-temperature-coefficient thermistor, the resistance would increase with temperature, which is not the case here. A zero resistance would imply a perfect conductor, which thermistors do not exhibit.