A platinum resistor has a resistance that changes with temperature. Values of the resistance were obtained experimentally for several temperatures from 5ºC to 30ºC only and plotted on the graph above. Design a procedure in which this resistor can be used as a thermometer to measure the temperature of a liquid that is in the 50ºC to 75ºC range. The resistor can be safely immersed in liquids. Along with the resistor and the container of the liquid of unknown temperature, the following equipment and materials may be used.
- Power supply
- Ammeter (Note: The ammeter and the voltmeter cannot be used directly as an ohmmeter)
- Voltmeter
- Connecting wires
- Ice-water bath
- Boiling-water bath
|