Heat & Temperature

Cool Hot Rod

COOL HOT ROD demonstrates that most materials expand when heated and contract when cooled. A long aluminum pipe can be heated or cooled by the visitor and its movement observed on an indicating dial, proving this principle. At higher temperatures, atoms vibrate more and take up slightly more space. A familiar application of this principle is the inclusion of expansion joints in bridge roadways. These gaps allow the bridge to expand and contract without cracking.



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