State the working principle of thermistors

State the working principle of thermistors 
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Answer :

A thermistor is a type of resistor whose resistance is dependent on temperature. Working principle: Whenever there is a change in temperature, the resistance of some semiconductors change . In case of PTC type, the resistance of the thermistor increases with increase in temperature. In case of NTC type, the resistance of the thermistor decreases with increase in temperature.
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