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J. Perelman
"Entertaining physics". Book 2.
Chapter 4. World attraction


Imagine the powerful attraction of the Sun for some reason really disappeared and the Earth will have the sad fate forever removed in the cold and gloomy desert of the universe. You can imagine, there are fantasy - that the engineers decided to replace the invisible chains of attraction material relationships, i.e. simply decided to connect the Earth with the Sun strong steel cables, which should keep the earth in a circular path in running around the Sun. What can be stronger than steel, capable of withstanding a tension of 100 kg per square millimeter? Imagine a powerful steel column, a diameter of 5 meters, the Area of its cross section concludes round score of 20 000 000 sq. mm; therefore, this column is broken only on the load of 2 000 000 tonnes. Imagine further that this column extends from the earth to the Sun, combining these two luminaries. Do you know how many of these mighty towers would be required to hold the Earth in its orbit? Million million! To better imagine the forest of steel columns, densely useualy all the continents and oceans, add that with a uniform distribution across the sunward half of the globe gaps between adjacent columns would be only slightly wider than the actual columns. Imagine the force needed to break this huge forest of steel columns, and you get an idea of the power of invisible forces of mutual attraction of the Earth and the Sun.

And all this enormous power is manifested only in the fact that, bending the path of motion of the Earth, every second causes the Earth to evade the tangent to 3 mm; this way our planet and turns into a closed, elliptical. Is it not strange that in order to move up the Earth every second of 3 mm, the height of this line is needed such huge force! This only shows how great mass of the globe, even if such a monstrous force can tell her only very slight movement.

Entertaining physics J. Perelman


System Orphus


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