Water science

Archimedes (287-212 BC), the Greek scientist and mathematician, once solved a very difficult problem simply by using water. The King of Syracuse believed that his new crown was not made from solid gold. He suspected his goldsmith had cheated him by adding silver to it. Archimedes filled three containers with the same amounts of water. In one container he put a lump of gold equal to the amount supposedly used in the crown. In the second, he placed the same amount of silver and in the third, he put the crown. The water level rose higher for the silver than for the gold. In the container with the crown, the water rose higher than the one with the block of pure gold so Archimedes knew that the crown must be a mixture of gold and silver.

The Archimedes principle