1. About Density:
Also called volumetric mass density, describes a substance's mass per unit volume, and can be calculated by dividing mass by volume.
2. Famous Story:
The most famous story about density is the one that Archimedes helps King Hiero to examine whether his golden wreath was adulterated or not.
Archimedes was so clever that he used a piece of pure gold having the same mass with the wreath, and put the gold and the wreath respectively into two same containers filled with water. Then he found that the amounts of the water spilled from the two containers were different - the one with wreath had spilled more.
This phenomenon reflected that the wreath had a larger volume than the gold with the same mass. At last, he drew the conclusion that the King's golden wreath was impure, because the density of the wreath (mass divided by larger volume) was lower than that of the pure gold (same mass divided by smaller volume).
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