Archimedes was a Greek scientist. He lives in Syracuse nearly 200 years ago. The King of the land wanted to wear a Golden Crown. He gave some gold to a goldsmith to make a suitable crown.
After few days, the goldsmith brought the finished crown to the King. The crown was weighed. The weight of the crown was equal to the gold given to the goldsmith by the King. The King looked at the colour of the crown. He had a suspicion. The goldsmith could have stolen some gold from the gold given to him.
The King wanted to find out the truth. He asked his court scientist Archimedes to find out. The King said, “Find out how much gold had been stolen?"
Archimedes slid into the bathtub. Immediately a large quantity of water flowed over the brim of the bath tub. He jumped out of the bathtub, shouting, “Eureka! Eureka!" Different metals of the same weight have different volumes. Objects, put in water, will displace water. The displaced water will be equal to their volume.
Archimedes took two bowls. He filled them with water to the brim. Then he placed each bowl separately in the middle of the large vessels. Archimedes then measured the quantity of water in the two vessels. He found out the difference in the water overflow. The crown had sent out more water. The cube of gold had sent out less water. But both the crown and the gold cube were of the same weight. So, they should have sent out the same quantity of water.
Archimedes reported this finding to the King. The King demanded the truth from the goldsmith. The goldsmith then confessed. He had stolen some gold. He had added some other metals.