Archimedes (Αρχ?μ?δη?, 287 BC - 212 BC), ancient Greek philosopher, mathematician, physicist, and scientist. Born in Syracuse, Sicily. Archimedes visited Alexandria. It is said that he invented the Archimedes screw pump while he was living in Alexandria, which is still in use in Egypt today. During the Second Punic War, the Roman army besieged Syracuse, and Archimedes died at the hands of Roman soldiers.

Life of Archimedes

Archimedes was born in 287 BC in the ancient city of Syracuse at the southeastern tip of Sicily, Greece. At that time, the glorious culture of ancient Greece had gradually declined, and the economic and cultural center gradually moved to Alexandria in Egypt; but on the other hand, the emerging Roman Empire on the Italian peninsula was also constantly expanding its power; there was also a new country in North Africa, Carthage. The foundation rises. Archimedes grew up in this era of alternation between old and new forces, and the ancient city of Syracuse became a place of struggle for many forces.

Archimedes’ father was an astronomer and mathematician, so he was influenced by his family since he was a child and loved mathematics very much. When he was about nine years old, his father sent him to study in Alexandria, Egypt. Alexandria was the intellectual and cultural center of the world at that time, with a large concentration of scholars. Research in literature, mathematics, astronomy, and medicine was very developed. Archimedes was Here he studied with many famous mathematicians, including the famous geometry master Euclid, which laid the foundation for his future scientific research.

After many years of studying, Archimedes returned to his hometown - Syracuse. It is said that the king of Syracuse, Heverlon II, was friends with Archimedes' father. Another theory is that the king was related to them. In short, after returning home, Archimedes was well received by the king. He often visited the palace and often chatted with the king and ministers about domestic affairs or state affairs. In this affluent environment, Archimedes conducted research work for several decades and made many important discoveries and achievements in mathematics, mechanics, and machinery, becoming the most innovative scientist in Europe in ancient times.

It is said that Archimedes often neglected food and sleep for research. When he walked into his residence, numbers and equations could be seen everywhere. The floor was covered with various graphics, and the walls and tables could not Those who were spared became his computing board, which shows his strong research spirit.

The king probably also knew about Archimedes’ amazing research spirit, so he gave Archimedes a difficult problem to solve.

You will know the real and fake crown with one try

This problem made Archimedes go home and think hard for several days, unable to eat or sleep well. It turned out that the king asked a goldsmith to make a pure gold crown from pure gold. After it was finished, the king suspected that the goldsmith was dishonest and might have faked it and mixed "silver" in it, but he could not destroy the crown to authenticate it. How can you test whether a crown is pure gold? Wow! This is a nerve-wracking question. Archimedes thought about it for a long time, but there was no good way.

One day, when he was taking a bath, he found that a lot of water overflowed when he sat in the tub, which made him think:

"The volume of the overflowing water is just right. It should be equal to the volume of his body, so just take the same weight of gold as the crown, put it in the water, measure its volume, and see if its volume is the same as the volume of the crown. If the volume of the crown is larger, that means where It's fake and adulterated."

When Archimedes thought of this, he couldn't help but happily jumped out of the bathtub and ran out naked, shouting "Eureka!" Eureka! (Greek: Discovered)” Don’t underestimate this sentence, the most famous invention fair in the modern world is named after “Eureka”. Sure enough, after it was proved that the crown did contain other impurities, Archimedes successfully exposed the goldsmith's trick, and the king was of course more convinced of him.

Later Archimedes further summarized this discovery into the theory of buoyancy and wrote it in his book "Theory of Floating Bodies", that is: the buoyancy force experienced by an object in a fluid is equal to the displacement displaced by the object The weight of the fluid. Archimedes established the basic principles of hydrostatics.

A Fulcrum Lifts the Earth

Archimedes’ research on machinery originated from his studies in Alexandria. One day Archimedes was walking along the dry Nile River and saw that farmers were struggling to carry water to irrigate their fields. After thinking about it, he invented a tool that used a spiral to rotate in a water pipe to suck water up. Later generations of people Call it the "Archimedes Spiral Water Lifter", and people in Egypt still use this device until now, two thousand years later. This tool became the ancestor of later propellers.

In Europe at that time, some simple machines were often used in engineering and daily life, such as screws, pulleys, levers, gears, etc. Archimedes spent a lot of time researching and discovered the "lever" The concepts of "principle" and "torque", for Archimedes who often used tools to make machinery, it was easy to apply the theory to practical life. He himself once said: "Give me a fulcrum, and I can lift the whole earth."

King Havilon just encountered another difficult problem: the king built a ship for King Ptolemy of Egypt Because the boat was too big and heavy, it couldn't be put into the sea. The king said to Archimedes, "You can even lift the earth. It shouldn't be a problem to put a ship into the sea, right?" So Archimedes immediately He cleverly combined various machines to build a machine. After everything was ready, he handed the rope to pull the machine to the king. The king gently pulled it, and the big ship moved and launched into the water. The king had to be convinced by Archimedes' genius. Impressed. From this historical story, we can clearly know that Archimedes was probably the person who had the most thorough understanding of the principles and applications of machinery in the world at that time.

Contemporary Mathematics Masters

For Archimedes, the research and invention of machinery and physics were only secondary. He was more interested and devoted more time to pure mathematics. Theoretical studies, especially in mathematics and astronomy. In terms of mathematics, he used the "approximation method" to calculate the area of ??the sphere, the volume of the sphere, the area of ??the parabola, and the area of ??the ellipse. Later mathematicians developed the modern "calculus" based on this "approximation method". He also studied the properties of spiral curves. The current "Archimedes Spiral" curve is named in his honor. In addition, in his book "The Art of Counting Sand", he created a set of methods for recording large numbers, which simplified the way of counting.

In astronomy, he once used water power to build a planetarium with the sun, moon, stars, and five planets on the spherical surface. According to records, this planetarium not only operated accurately, but also accurately determined when a lunar eclipse would occur. Solar eclipses can be predicted. In his later years, Archimedes began to doubt the geocentric theory and speculated that the earth might revolve around the sun. This concept was not discussed until the time of Copernicus.

If Archimedes had continued his research, his achievements would have been even more limitless. Unfortunately, he was killed in 212 BC when he was 74 years old.

The end of the third century AD was the period when the Roman Empire and the North African Carthage Empire fought for hegemony in Sicily. Syracuse, which was located in Sicily, had always defected to Rome, but in 216 BC Carthage defeated the Roman army. The new king of Syracuse (successored by the grandson of Javiron II) immediately changed course and formed an alliance with Carthage. , the Roman Empire sent General Marcellus to lead an army to attack Syracuse by sea and land at the same time. Archimedes saw that the country was in danger, and his sense of responsibility to protect the country prompted him to rise up and fight against the enemy. So he racked his brains and worked day and night to invent and defend against the enemy. arms.

According to some later records, at that time he built a huge crane that could lift enemy warships into the air and then drop them so hard that the warships shattered on the water; he also used the lever principle to create A group of trebuchets were sent out, and any enemy close to the city wall would not be able to escape his flying stones or javelins.

These weapons made the Roman army panic and everyone was afraid. Even General Marcellus admitted with a wry smile: "This is a war between the Roman fleet and Archimedes alone." Archimedes is the mythical giant with a hundred hands.”

Due to being unable to attack for a long time, Marcellus changed his strategy and used a protracted siege to cut off the food in the city. This clever plan made Archimedes helpless. In 212 BC, Syracuse was finally conquered by the Roman army. It is said that when the Roman army entered the city, Archimedes was drawing pictures on the ground in front of his house to study geometric problems. A Roman soldier approached Archimedes who was meditating and trampled the figures drawn on the ground. Archimedes said: "Stand away, don't step on my figure!" The soldier was very angry when he heard this, so he pulled out his knife and stabbed Archimedes, and the great scientist died.

Marcellas was very sad when he heard the news, so he built a tomb for Archimedes engraved with circles and balls to express his respect for this great scientist and great opponent. of respect. ~~

The story of taking a bath

There is such an interesting story about Archimedes. According to legend, King Hernon of Syracuse asked a craftsman to make a pure gold crown for him. After it was completed, the king suspected that the craftsman had adulterated the gold crown, but the gold crown was indeed as heavy as the pure gold originally given to the goldsmith. , did the craftsmen do anything wrong? Wanting to test the authenticity without destroying the crown, this problem not only stumped the king, but also made the ministers look at each other.

Later, the king asked Archimedes to inspect it. At first, Archimedes also thought hard but couldn't figure it out. One day, he went to the bathhouse to take a bath. When he sat in the tub, he saw water overflowing and felt his body being gently pulled up. He suddenly realized that he could determine the specific gravity of the gold crown by measuring the displacement of a solid in water. He jumped out of the bathtub excitedly and ran out without even taking care of his clothes, shouting "Eureka! Eureka!". (Eureka, meaning "I know").

After further experiments, he came to the palace. He placed the crown and the same weight of pure gold in two basins filled with water. One basin overflowed with more water than the other basin. This shows that the volume of the crown is larger than that of pure gold of the same weight, so it proves that other metals are mixed into the crown.

The significance of this experiment is far greater than finding out that the goldsmith deceived the king. Archimedes discovered the law of buoyancy: the buoyancy gained by an object in a liquid is equal to the weight of the liquid he displaced. Later, this law was named Archimedes' law. Until modern times, people are still using this principle to calculate the specific gravity of objects and determine the load capacity of ships.

Archimedes the Patriot

In Archimedes’ later years, the Roman army invaded Syracuse. Archimedes guided his compatriots to create many offensive and defensive operations. arms. When Marcellus, the leader of the invading army, led his troops to attack the city, he designed a trebuchet that beat the enemy to tears. The iron claw crane he built could lift and reverse enemy ships...

Another incredible legend is that he once led the people of Syracuse to hold a concave mirror and focus the sunlight on the Roman army. wooden warships and set them on fire. The Roman soldiers were frightened by these frequent blows, and the trees and grass were all in disarray. As soon as they saw ropes or logs being thrown from the city, they exclaimed "Archimedes is coming" and ran away with their heads in their hands.

The Roman army was held back from the city for three years. Finally, in 212 BC, the Romans took advantage of the slight laxity in the defense of the ancient city of Syracuse and launched a massive attack into the city. At this time, the 75-year-old Archimedes was concentrating on studying a profound mathematical problem. A Roman soldier broke in and trampled on the figure he had drawn. Archimedes argued with him angrily. The cruel and ignorant soldier raised his knife. With a wave of his hand, a bright scientific star fell.