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Archimedes needed to determine if a goldsmith had embezzled gold during the manufacture of the royal crown for King Hiero I of Syracuse . How would you find out if a crown was made of gold or a cheaper alloy ? How would you know if the crown was a base metal with a golden exterior ? Gold is a very ____________________ metal ( even heavier than lead , though lead has a higher atomic ____________________ ) , so one way to test the crown would be to determine its density ( mass per unit ____________________ ) . Archimedes could use scales to find the ____________________ of the crown , but how would he find the volume ? Melting the crown down to cast it into a cube or ____________________ would make for an easy calculation and an angry king .
After pondering the problem , it occurred to Archimedes that he could ____________________ volume based on how much water the ____________________ displaced . Technically , he didn't even need to weigh the crown , if he had access to the royal treasury since he could just compare the displacement of water by the crown with the displacement of water by an ____________________ volume of the gold the smith was given to use . According to the story , once Archimedes hit upon the solution to his problem , he burst outside , naked , and ran through the streets yelling , " ____________________ ! ____________________ ! "
Some of this might be fiction , but Archimedes' idea to calculate the ____________________ of an object and its density if you know the object's weight was fact . For a small object , in the lab , the easiest way to do this is to partly fill a graduated cylinder large enough to contain the object with water ( or some liquid in which the object won't dissolve ) . Record the volume of water . Add the object , being careful to eliminate air bubbles . Record the new volume . The volume of the object is the initial volume in the cylinder subtracted from the final volume . If you have the object's mass , its density is the mass divided by its volume .