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    Re: Need dip-throw a rock?
    From: Frank Reed
    Date: 2011 Jun 22, 21:17 -0700

    Tom you asked:
    "For a relatively higher bridge would you expect a larger or a smaller

    The same! It's a simple proportionalty: dip=4*time (dip in minutes of arc, time in seconds). So think about it: if you have a tenth of a second error in the fall time, you get an error of 0.4' in the dip, no matter how high you are. Eventually, though, at seriously high altitudes, any dropped object, even a nicely aerodynamic spike of depleted Uranium (everybody should keep a few handy), will be significantly affected by air resistance, and the simple proportionality rule will no longer apply. I would like to experiment with this, but based on calculations, I think you can trust the rule up to about 200 feet with a two-inch diameter, round, fairly dense rock.


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