Development of a Thermometer Using Thin Film Platinum Sensor for Science Education and its Applications

Abstract

A thermometer using two thin film platinum sensors (resistance is 10Ω at 50℃) has been developed for science education. The thin film sensor has small heat capacity and resistance changes fast with temperature. Therefore, temperature response is good. Both temperature and temperature difference between two the sensors can be measured simultaneously by using bridge circuits in which the resistance of lead wires of the sensors is compensated. Measurement error is; within +0.2℃ in the temperature range from 0.0 to 50.0℃. This thermometer has been applied to the measurements of temperature changes in adiabatic expansion of air and in coagulation of water. In each case, favorable results were obtained for use as a teaching tools.