Have you ever wonder , how our ancestors discover that the earth is a round sphere revolving round the sun in eliptical orbits and that a year contains 365.25 days . They even presicely calculated the time of sunrise, sunset, solar and lunar eclipse. They did all this thousands of years ago without any modern technology. Now we live in an age where multi million dollar machinery are looking of God particle worth discovering particles which may travel faster than light. And all of these discoveries are made possible by technology that was developed in last few decades but for most of the human history, we had to discover these using our eyes, ears and our minds.
Born around 276 B.C. in Cyrene, Eratosthenes is best known for first recorded measurement of the Earth’s circumference. He worked in the library of Alexandria, where he read about a curious event that took place in Syene at the summer solstice. At high noon, the sun would shine directly overhead and there would be no shadows of the columns. However, Eratosthenes know that at the same moment in Alexandria, clearly did have shadows. Being a good mathematician, he used this knowledge to do a few calculations to figure out the circumference of the Earth. For this, Eratosthenes measured the shadow of a stick at noon. He discovered that the sun was about 7°14’ from being directly overhead. Furthermore, he knew that a circle measures 360°, which says that the angle of the shadow i.e., 7°14’ was roughly one fiftieth of a circle. So if
Eratosthenes multiplied the distance between Syene and Alexandria by 50, he would have the circumference of the Earth. Not only this, even the speed of the light is calculated without using any modern technology.
Coming to the calculation of the speed of the light, first it was believed that light’s speed is infinite .Later the first quantitative measurement of the speed of light is determined by Galelio, he found that its speed is roughly > 30km/sec or may be that speed of light is nearly 10 times greater than sound.
Another Physicist called Armond Fezeau, who is familiar with Galelio’s experiment on determination of light equiped a toothed wheel to split the light, a solution to send descrete pulses of light and thus determined the speed of the light 1.05% greater than the actual value.
Summary:
People that made these discoveries are not equiped with modern technology, they just thought a little bit harder about what they are looking at & more
curious and their curiousity changed how people thought about the world and thus they changed the world and so can you.
References : https://en.wikipedia.org/wiki/Eratosthenes
https://en.wikipedia.org/wiki/Speed_of_light
Born around 276 B.C. in Cyrene, Eratosthenes is best known for first recorded measurement of the Earth’s circumference. He worked in the library of Alexandria, where he read about a curious event that took place in Syene at the summer solstice. At high noon, the sun would shine directly overhead and there would be no shadows of the columns. However, Eratosthenes know that at the same moment in Alexandria, clearly did have shadows. Being a good mathematician, he used this knowledge to do a few calculations to figure out the circumference of the Earth. For this, Eratosthenes measured the shadow of a stick at noon. He discovered that the sun was about 7°14’ from being directly overhead. Furthermore, he knew that a circle measures 360°, which says that the angle of the shadow i.e., 7°14’ was roughly one fiftieth of a circle. So if
Eratosthenes multiplied the distance between Syene and Alexandria by 50, he would have the circumference of the Earth. Not only this, even the speed of the light is calculated without using any modern technology.
Coming to the calculation of the speed of the light, first it was believed that light’s speed is infinite .Later the first quantitative measurement of the speed of light is determined by Galelio, he found that its speed is roughly > 30km/sec or may be that speed of light is nearly 10 times greater than sound.
Another Physicist called Armond Fezeau, who is familiar with Galelio’s experiment on determination of light equiped a toothed wheel to split the light, a solution to send descrete pulses of light and thus determined the speed of the light 1.05% greater than the actual value.
Summary:
People that made these discoveries are not equiped with modern technology, they just thought a little bit harder about what they are looking at & more
curious and their curiousity changed how people thought about the world and thus they changed the world and so can you.
References : https://en.wikipedia.org/wiki/Eratosthenes
https://en.wikipedia.org/wiki/Speed_of_light
