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The reason that Archimedes could not raise the Earth
"Give me a fulcrum and I will lift the Earth," said the great mechanic ancient Archimedes. Indeed, choosing the right arm, in theory, can lift a load of any severity. However, the reality is more complicated. So why gamble great scientist could not succeed?
If Archimedes knew how much weight our planet, he probably would have been more restrained in his statements. To date, the mass of the Earth - known quantity and is 6 × 1024 kg. Assume that there is a fulcrum and lever desired length. If a person is able to lift 60 kg, it would need a lever long arm is greater than the short time in 1023. And now - a simple arithmetic. To raise the Earth at a height of 1 cm, the opposite end of the lever must describe an arc length of 1018 km. Let us assume that Archimedes able to lift 60 kg to a height of 1 m in 1 s (operation in the whole horsepower) while lifting the earth 1cm he would take neither more nor less - 30 trillion years. As you know, our universe is much less - only 16 billion years old. Even if a scientist would be pulling the lever at the speed of light, still, it would have to operate continuously 10 million years.
Never forget the golden rule of mechanics, which states that any gain in strength leads to a loss in speed and therefore in time. If somewhere something will come somewhere necessarily lose anything.
The article is based on the book by Perelman YI "Entertaining Physics". Book Two. 1932
via factroom.ru
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