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the drunken engineer

A system was set up and analyzed for the purpose of determining the resistance characteristics of copper (a metal), germanium (a semiconductor) and a standard resistor as temperature changes. This will be done by applying a current through each of the materials at different temperatures, ranging from 123K to 423K, while recording the voltage drop across each substance. This data was analyzed to find the coefficient of resistivity for copper: 450.86 1/K, using a linear regression on a plot of current verses voltage and comparison to the resistance equation for a metal. The energy gap of the germanium semiconductor was found to be 0.725eV, a 9.0% deviation from the accepted value of 0.741eV. As was expected, the maximum percentage change in the value of resistor was 0.1%. These minor deviations can be mostly attributed to a load on the circuit produced by wiring and terminals, and a temperature that varied (even with the temperature control device activated) during the course of a set of measurements. Also, incorrect or inaccurate calibration of the thermometer or incomplete immersion would have a negative effect on any data collected.