This Greek engineer is immortalized in history books as having run through the Syracuse streets naked, shouting “Eureka,” which simply translates to “I have it.” The story behind this unusual event was that he had been commissioned to prove that a new crown for the King of Syracuse (Hieron) was not made of pure gold as it had been claimed by a goldsmith. Although it took Archimedes a hell of time thinking, he wasn’t able to come up with a method to provide the needed proof.

On one occasion, he filled a bathtub with water and realized that the water was spilling over the edge of the tub as he got in. In no time, he noticed that the displaced water was equal to his body weight. Now, having known that gold was heavier that other metals in the crown, Archimedes had already nailed down a method to prove that the king’s crown was not solid gold. He quickly got out of the bathtub and ran to the King, shouting “Eureka”. Of course, he had forgotten he was naked because the discovery was a huge one.

## The Archimedes Principle and Its Uses

The principle states that when an object is submerged in water, its buoyant force equals the weight of the displaced water. For instance, when you add ice cubes to a glass full of water, the water will spill over the edge of the glass just like it did when Archimedes entered the tub. If the displaced water is weighed (weight refers to a downward force), it will be equal to the buoyant (upward force) on the object (ice cubes). Once you have the buoyant force, you can determine the average density or volume of an object.

Today, the Archimedes principle is a critical and versatile tool. It is applied in finding the volume of irregular objects and explaining the behavior of objects when placed in a fluid. This principle explains how submarines are able to dive in water, how hot air balloons fly in the air, and how ships float on water. Additionally, the Archimedes principle is used in engineering, geology, entomology, and many other scientific research subjects.

## Other Achievements

Alongside the Archimedes principle, Archimedes:

- Invented the sciences of hydrostatics and mechanics.
- Invented the center of gravity, which is regarded as the most critical concept in physics.
- Discovered and proved the formulas for finding the surface area and volume of a sphere.
- Came up with the Archimedean Screw, which is useful in pulling water from the ground today.
- Invented war machines, including a catapult, which saved Syracuse from the Roman conquest for many years. The catapult was so accurate that it is thought to have been created based on projectile trajectory mathematics.

In summary, Archimedes is recognized by many people as the greatest classical engineer. He had immense influence in physics, mathematics, astronomy, and engineering. Although very little is known about his life, his scientific discoveries are still helpful to this day. Indeed, he is a true definition of an engineering legend.