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Eleatic Guest
Guest
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If I had a scanner, I would have scanned the whole article by now and uploaded it, but unfortunately I have no yet. Perhaps somebody else can do and mak it a pdf, I think it is very much worth the effort.
Air drag is calculated: R = Cw x D/2 x V squared x Q
R : airdrag in Newton (Luftwiderstand in Newton) V : speed of projectile (Geschossgeschwindigkeit) Q : width of projectile, seen from the ballistic curve, m squared (Geschossquerschnitt, aus der Bahnrichtung gesehen, m zum Quadrat) D : air density, kg/cbm (Luftdichte) Cw : resistance value, a mere multiplication factor (dimensionless number), depends on the shape of the projectile (Widerstandsbeiwert, ein reiner Multiplikationsfaktor (dimensionslose Zahl), haengt von der Form des Geschosses ab
As for the range issue: The author makes a point of differing between maximal range, sports record ranges as he calls it, and militarily effective ranges. His key consideration is that, the longer the range, the smaller the hit probability. "Already small angle deviations at throwing change the ballistic curve over long distances considerably", as the winddrift increases. That, of course, applies only to individual, but not to mass targets, as he stresses. As I already said, the author is more complex than I can reflect here, he tries to consider things from every angle, thats why I would recommend the article so strongly.
As for maximal range: The author gives some numbers, but he makes again a point that the maximal ranges which he presents are a function of the values he has defined. With a projectile of 40g, throwing speed of 75m/s (=112,5 Joule), a throw angle of 40 degrees, air density of 1,14kg/cbm and a resistance value of 0,4 the maximal ranges are:
lead 352 m stone 232 m clay 200 m
At these distances, lead hits home with 42% of the initial 112,5 joule projectile energy, stone with 23%, and clay with 19%.
-> Lead can not only be thrown the farthest, it also has even though it travels longer in the air, the highest impact.
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