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Weekend


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November 1, 2002

Strange But True!

  • A weekly column of incidental information, off-the-wall observations and other random facts about the world.
    • By BILL SONES and RICH SONES, Ph.D.
    Special to the Journal

    Q. Suppose you're "sack-drop engineer" on a goodwill flight to deliver bags of flour to flood-ravaged hinterlands. To land the food on target, you must know that ... a) a sack falls straight down to ground beneath the release point, because the plane flies on after the drop is made b) a sack will fall well behind the release point, having been pushed backward by onrushing air c) a sack will fall far in front of the release point, carrying along the plane's horizontal velocity all the way to the ground?

    A. c) A sack falls in a curved trajectory, reaching about 30 meters/second for a 3-second drop from 50 meters up, says Keith Lockett in "Physics in the Real World." The sack will land well in front of the release point, much closer to where the plane will then be than to where it was at drop-time.


     
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