Temperature is best judged using some external reference, such as the expansion or contraction of a liquid. Two temperature scales, the Celsius and Fahrenheit, are demonstrated. Duration: 6:05.
VIDEO CHECK QUESTIONS
2.8a What principle is a typical thermometer based upon?
2.8b Why does the Fahrenheit scale have 212° as the boiling point of water?
2.8c What two liquids are commonly used to make a thermometer?
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