In 240 BC, the Greek astronomer, geographer, mathematician, music theorist, and librarian Eratosthenes of Cyrene (c. 276 BC – c. 195/194 BC) calculated the circumference of the Earth without even leaving Egypt. Here’s how:
Category Archives: Physics
How Earth Moves (Video)
A beautiful video, once again, from Michael Stevens, titled “How Earth Moves”. Michael explains many concepts, including “sub-solar point”, “sidereal day vs solar day”, or “how Earth moves in the space” etc, and he is doing it in a very simplified manner. Enjoy!
Are we the first spacefarer civilization? New study says maybe
Can we, humans, be one of the few (or the only) civilizations in the Universe that surpassed the so-called “great barrier”? Are we the first?
No! The Earth Would NOT Look Like This Without Water
The Earth would NOT look like this without water. Please stop sharing this nonsense. Here are some numbers: the Earth has a diameter of about 12,735 kilometers (on average). The highest point on Earth is the top of Mount Everest, at 8,848 meters (29,029 feet). The deepest point on Earth is the Mariana Trench, at …
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Bowling ball and feather fall in a vacuum at the exact same speed. Here’s why.
The English physicist Brian Cox tests how a heavy object (a bowling ball) and a lightweight object (feather) fall in a vacuum – if they fall at the exact same speed or not.
