Development of a remotely operable experiment for teaching thermometry: a method for determining the coefficient of linear expansion based on the Joule effect

This paper presents the “Thermometry”, a remotely controlled experiment. We discuss the aspects of the project according to its main areas of development, i.e. the physical structure of the experiment, hardware, and software. The theoretical model for determining the coefficient of linear expansion is discussed in detail. The determination of the coefficient of linear expansion has shown a relative deviation up to 7%, in the module, for heating times equal to or lower than 3 seconds, lowering down to 2% for times equal to 1 second. For values greater than 3 seconds howbeit, these deviations assume significant values, reaching up to 75% for heating times of 10 seconds. Based on these results, some improvements could be drafted, for example, putting the experiment inside an isolated container in order to mitigate the effect of drafts in the lab, lowering thus the environment’s thermal conductivity, and enhancing the accuracy of the temperature measurements. These enhancements are to be implemented in the future. From the didactic point of view, the experiment allows a variety of approaches for many different educational levels. Some remarks are presented on this matter.

Keywords:
Experimental activities; remote experiments; thermometry; Joule effect