A thermistor is an electronic resistance exhibiting strong temperature dependence.  NTC thermistors are negative temperature coefficient resistances, the resistance of which declined with the rise of temperature, therefore it can be used to measure temperature. By measuring the changes in the resistance level you can infer to the temperature. Attach the thermistor to a multimeter and bring to equilibrium using waters of different temperature, so that hot water is gradually cooled down by the addition of cold water. Once the position of the thermometer does not change any more, take the reading and the associated resistance level. Pairs of resistance and temperature included in a table are displayed on an R-T graph. The characteristic resistance-temperature curve received is regarded as the calibration graph of the thermistor thermometer! Use the multimeter in a resistance measuring operating mode (measuring limit on the picture is 200 Ω). The calibration graph can be used to determine any unknown temperature from the related resistance level.

Implements required for the experiment

– Glass vessel
– Thermometer
– Multimeter set to measure resistance
– NTC (negative temperature coefficient thermistor)
– Shrinkable tube for insulation (the thinnest)
– Water, water heater