A REAL TALE OF SCIENCE ABOUT CURIOSITY AND CREATIVITY
Published on Jun 25, 2018
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PRESENTATION OUTLINE
More than 2000 years ago, Greeks observed that ships disappeared in the horizon. WHY?
Photo by BRUNO CERVERA
And this famous mathematician
observed that in Syene, Egypt, on SOLSTICE day, the Sun was exactly over his head!
Photo by Clint McKoy
At noon, objects cast NO SHADOW!
But in Alexandria (800 km away)
SOMETHING DIFFERENT HAPPENED!
Objects cast a 7.2 ° shadow, but WHY?
Here’s Eratosthenes’ reasoning:
1) The Earth surface must be ROUND
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2) Knowing the angle of the shadow, he used simple geometry:
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AND... EUREKA!!
The circumference of the Earth was calculated:
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TODAY, WITH MODERN TECHNOLOGY, WE KNOW THAT THE REAL CIRCUMFERENCE OF EARTH is about 40070 km
BUT WHAT DOES THE STORY TEACH US? (other than the scientific aspect?)
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Photo by jepoirrier
