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Several reasons for which the heroes of Jules Verne would not have to fly to the moon from a cannon
Many are familiar with the novel by Jules Verne's "From the Earth to the moon right way for 97 hours and 20 minutes", which the unfolding events in the United States after the Civil War. The hero of the novel Impey Barbicane set about trying to create a gun, which is manned round after a shot could reach the moon and bring back passengers. Although the plot of Mr. Barbikenu able to realize his adventure in life, there are actually a number of reasons why this is the reality of the company could not succeed.
Having received a carte blanche, the novel's characters cast a huge, long-quarter kilometer gun. Cannonball used as cabins for passengers, weighs 8 tons. The explosion of the charge, according to the novelist, the core has a maximum speed of 16 km / s, but because of the friction with the air speed is reduced to 11, 2 km / s. That is, the shell develops escape velocity sufficient to overcome the Earth's gravity, and freely moving in the direction of the moon. These figures result in his novel by Jules Verne. And what about this says physicist? So the reasons for such a venture would have suffered a fiasco.
The first reason - this monstrous acceleration. To get up to speed from 0 to 16 km / s, while the kernel has not left the gun barrel, its acceleration should be 600 km / s2. As is known, the acceleration of gravity on Earth is 10 m / s2, t. E. Overload passengers will increase to 60 thousand. Times. One only Mr. Barbecue hat would weigh 15 tons. Therefore, in the first fraction of a second the passengers just smear on the floor. Yes, and the hollow shell is unlikely to survive such overload. There are ways to ease the congestion? A man without serious consequences can withstand short-tenfold increase in acceleration. But to ensure that such conditions will have to lengthen the barrel of the gun up to 6 thousand. Km. And in this case it will have to dig right up to the very core of the Earth.
The second reason - severe overheating. If the passengers survived the acceleration that is absolutely impossible, they would have died from overheating arising during friction of the projectile on the air.
Reason Three. Author of the novel did not provide any means for lunar landing. Therefore, if the projectile safely reach the Moon, it will break on its surface. And sending from the moon to Earth in case of a successful lunar landing, too, was not provided.
You can find many more reasons why this journey is not guaranteed to succeed. But these three reasons enough to make the flight even in hopeless adventure and guaranteed suicide.
Although Jules Verne, and did not consider a number of factors, he first of all science fiction writers deeply and seriously used the modern scientific knowledge for him.
Perelman YI Entertaining physics. Book Two. 1932
via factroom.ru
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