Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/17/84; site hao.UUCP Path: utzoo!watmath!clyde!burl!ulysses!allegra!mit-eddie!godot!harvard!seismo!hao!hull From: hull@hao.UUCP (Howard Hull) Newsgroups: net.physics Subject: Re: Floating a battleship in a gallon of water Message-ID: <1301@hao.UUCP> Date: Wed, 12-Dec-84 09:46:59 EST Article-I.D.: hao.1301 Posted: Wed Dec 12 09:46:59 1984 Date-Received: Fri, 14-Dec-84 05:37:59 EST References: <27@daisy.UUCP> <6235@mcvax.UUCP> Distribution: net Organization: High Altitude Obs./NCAR, Boulder CO Lines: 27 During the night it finally dawned on me what must be done. Assuming that one gets the battleship to float using any suitable configuration, it is possible to place a valve in the connecting channel and close it without any resultant redistribution of the forces. After that is done, then we may indeed remove the water and the battleship will continue to float in its gallon of water. One way to avoid problems in teaching this would be to restate the principle of Archimedes thusly: "If an object is freely suspended in a liquid, it is buoyed up by a force equal to the weight of the displaced liquid, or its virtual equivalent." So as you can see, I AM STILL serious about requiring the 100,000 tons of water to be there even if it is in a virtual form, or as you put it, not "really" there. Please let me apollogize in advance if I confused anyone by my incomplete statement of the situation. So now I have a question. If we now wish to squeeze all of the water out of the gap between the battleship and trough wall, what force pressing down on the ship will be required to do so? If we can get that question answered, then we can find an answer to the original question in its proper context... The original question was "how can the water hold up something greater than its own weight". This would seem to be a question of fundamental structure were it not for the degree of freedom allowed by the width of the space between the ship and the trough. Regards, Howard Hull {ucbvax!hplabs | allegra!nbires | harpo!seismo } !hao!hull