The resistance of a thermistor ... as its temperature rises:

The resistance of a thermistor decreases as its temperature rises because of the intrinsic properties of the material it is made from. Thermistors are typically made from semiconductor materials that have a negative temperature coefficient (NTC). This means that as their temperature increases, the number of charge carriers (electrons and holes) available for conduction also increases. Consequently, this increase in charge carriers leads to decreased resistance.

In practical applications, thermistors are widely used in temperature sensing and control systems due to this characteristic. When the temperature around the thermistor rises, the decrease in resistance can be measured and utilized by electronic circuits to infer the temperature change accurately. This property is crucial in applications like temperature measurement in HVAC systems, automotive sensors, and various consumer electronics, ensuring effective monitoring and regulation of temperatures.