Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/18/84 +MMDF+2.11; site ukc.UUCP Path: utzoo!watmath!clyde!cbosgd!ihnp4!qantel!dual!lll-crg!seismo!mcvax!ukc!djw1 From: djw1@ukc.UUCP (D.J.Webb) Newsgroups: net.physics Subject: Re: Monkey Query and new problem Message-ID: <350@ukc.UUCP> Date: Tue, 5-Nov-85 12:50:49 EST Article-I.D.: ukc.350 Posted: Tue Nov 5 12:50:49 1985 Date-Received: Sun, 10-Nov-85 08:51:13 EST References: <705@sri-arpa.ARPA> <661@petrus.UUCP> <10855@ucbvax.BERKELEY.EDU> <668@petrus.UUCP> Reply-To: djw1@eagle.UUCP (Dave Webb) Organization: U of Kent at Canterbury, Canterbury, UK Lines: 17 In article <668@petrus.UUCP> mwg@petrus.UUCP (Mark Garrett) writes: > >Somebody here said they saw a film about the Lindburg flight where old >CL was flying along, bored, and noticed a fly inside the plane. He >started wondering if the mass of the fly contributed to the weight >of the plane. If the fly is sitting on something then obviously it does. >But what if the fly is flying around? What if the fly is falling? Does it >make a difference if the plane is airtight or not? Wether the fly is sitting on something or flying, it still contributes to the weight of the plane, since any downward force it exerts to keep itself airborn must eventually be comunicated to the plane. This reminds me of a similar problem concerning an aquaduct which is just strong enough to support the weight of water in it; if a barge sails onto the aquaduct, will it collapse? Work it out for yourselves! Cheers, Dave Webb