Eureka! The Archimedes PrincipleArchimedes was possibly the world's greatest scientist — at least the greatest in the classical age. He was a physicist, mathematician, astronomer, inventor and engineer. Many of his inventions, theories and concepts are still in use today. Perhaps his best-known achievement was his "Eureka" moment, when he discovered the principle of buoyancy.
'Eureka! Eureka!'
Archimedes has gone down in history as the guy who ran naked through the streets of Syracuse shouting "Eureka!" — or "I have it!" in Greek. The story behind that event was that Archimedes was charged with proving that a new crown made for Hieron, the king of Syracuse, was not pure gold as the goldsmith had claimed. The story was first written down in the first century B.C. by Vitruvius, a Roman architect.
Archimedes thought long and hard but could not find a method for proving that the crown was not solid gold. Soon after, he filled a bathtub and noticed that water spilled over the edge as he got in and he realized that the water displaced by his body was equal to the weight of his body. Knowing that gold was heavier than other metals the crown maker could have substituted in, Archimedes had his method to determine that the crown was not pure gold. Forgetting that he was undressed, he went running naked down the streets from his home to the king shouting "Eureka!"
The Archimedes principle
According to Boundless, the Archimedes principle states that the buoyant force on an object submerged in a fluid is equal to the weight of the fluid that is displaced by that object.
If a glass is filled to the top with water and then ice cubes are added to it, what happens? Just like the water spilled over the edge when Archimedes entered his bathtub, the water in the glass will spill over when ice cubes are added to it. If the water that spilled out were weighed (weight is a downward force), it would equal the upward (buoyant) force on the object. From the buoyant force, the volume or average density of the object can be determined.
Archimedes was able to determine that the crown was not pure gold due to the volume of the displaced water, because even though the weight of the crown was identical to the weight of the gold that the king gave the crown maker, the volume was different due the various densities of the metals.
Uses of the Archimedes principle
The Archimedes principle is a very useful and versatile tool. It can be useful in measuring the volume of irregular objects, such as gold crowns, as well as explaining the behaviors of any object placed in any fluid. Archimedes' principle describes how ships float, submarines dive, hot air balloons fly, and many others examples, according to Science Clarified. The Archimedes principle is also used in a large variety of scientific research subjects including medical, engineering, entomology, engineering, and geology.
