2018 BFY III Abstract Detail Page
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||W10: Thermoelectric Effect and Applications-An Electronics ‘Final Project’ Experiment
||Thermoelectric cooling and heating have many applications in modern technology and are quite fruitful to utilize and study in physics advanced labs.
This workshop will implement and investigate inexpensive 'Peltier cooling plates' in: 1) super-cooling/flash-freezing of water droplets, 2) Verifying the temperature dependence of the resistance of a metal and a semiconductor and using that to estimate the energy gap in the semiconductor, 3) using a temperature gradient to generate a voltage (Seebeck effect). This set of experiments emphasizes design and scientific investigation, while also developing some of the main goals of advanced laboratories as the exposure to experimental skills and techniques, data collection and automation/control as well as data analysis and the clear communication of the results.
We will place a thin thermocouple into a water droplet that is placed on the cold plate and monitor the temperature directly as the droplet cools well below zero and then freezes promptly giving a unique temperature profile both when it freezes and when it melts at warm-up. We will also place a long, thin, loop-shaped 'magnet wire' on the clod/hot plate and measure its resistance variation with temperature, which turns out to be linear, consistent with phonon scattering. On the other hand, the temperature variation of the resistance of a thermistor has a very different behavior and will be used to directly extract the energy gap between the valence and conduction bands. We will also talk about extra experiments that students proposed in our own teaching lab, like applying a temperature gradient across the plates and measuring the generated power, using a solar panel to power the plates, or using Arduino to monitor the temperature and give a warning when it is outside a given range.
6150 Fairfield Rd
Oxford, OH 45056