c160-3ay@ucbzooey.BERKELEY.EDU (Banquo's Ghost) (10/31/85)
Subject: infinitesimal bees Newsgroups: net.puzzle Here's one from a highschool physics class: At time 0, two cars are 5 miles apart, headed directly towards each other, each moving at 20 miles per hour. (The speed remains constant throughout the problem.) At time 0, a fast bee flies from one car towards the other. As soon as it reaches the other car, it turns around in infinitesimal time and heads back towards the first car. And so on. This bee flies at 30 miles per hour. How far does the bee travel before being demolished in the eventual collision? ...Ranjit
ejnorman@uwmacc.UUCP (Eric Norman) (11/01/85)
On any planet where bees can turn around in infinitesimal
time, cars are frictionless and not allowed on the equator
(John von Neumann told me this personally). Therefore,
the bee is still flying. They did teach you about the
Coriolis force in high school, didn't they?
--
Eric Norman
UUCP: ...{allegra,ihnp4,seismo}!uwvax!uwmacc!ejnorman
Pony Express: 1210 West Dayton Street, Madison, WI 53706
Life: Detroit!Alexandria!Omaha!Indianapolis!Madison!Hyde
"Up with levity; down with gravity." -- me
gwyn@brl-tgr.ARPA (Doug Gwyn <gwyn>) (11/01/85)
> On any planet where bees can turn around in infinitesimal > time, cars are frictionless and not allowed on the equator > (John von Neumann told me this personally). Therefore, > the bee is still flying. They did teach you about the > Coriolis force in high school, didn't they? Does it matter whether the bees turn left or right? Oh, oops, wrong problem.. Really, this bee business is equivalent to the fly and the bicycles and several other standard statements of this puzzle and was beaten to death (I thought) in this newsgroup not very long ago. Could we please not keep posting puzzles out of the stock puzzle books? Thanks..
c160-3ay@ucbzooey.BERKELEY.EDU (The Grinch) (11/03/85)
>Really, this bee business is equivalent to the fly and >the bicycles and several other standard statements of >this puzzle and was beaten to death (I thought) in this >newsgroup not very long ago. Could we please not keep >posting puzzles out of the stock puzzle books? Thanks.. Oops! Well, excuse me! I didn't see this problem on the newsgroup, nor have I ever seen it in any puzzle book. So, why didn't someone tell me BEFORE I sent the message? (-:) Alright then, what common english word is invariant under the alphabet transformation of A-Z, B-Y, C-X, etc.? ...ranjit
grady@ucbvax.BERKELEY.EDU (Steven Grady) (11/03/85)
In article <10886@ucbvax.BERKELEY.EDU> c160-3ay@ucbzooey.UUCP (The Grinch) writes: > >Alright then, what common english word is invariant under the alphabet >transformation of A-Z, B-Y, C-X, etc.? Why, obviously "rmezirzmg"! (ie "I was walking down the street and someone had sprayed 'rmezirzmg' in a wall.") Steven PS I hate smiley faces.. If you couldn't guess that this was not serious, why Lick a baseball bat-eating buzzard's brain! You dog dodo-infested eyed axe murderer! You should have sex with a dodo rectumed rust monster.
dave@circadia.UUCP (David Messer) (11/05/85)
> At time 0, two cars are 5 miles apart, headed directly towards each > other, each moving at 20 miles per hour. (The speed remains constant > throughout the problem.) > > At time 0, a fast bee flies from one car towards the other. As soon > as it reaches the other car, it turns around in infinitesimal time > and heads back towards the first car. And so on. This bee flies at > 30 miles per hour. > > How far does the bee travel before being demolished in the eventual > collision? That's easy. 3.75 miles. -- David Messer UUCP: ...ihnp4!circadia!dave FIDO: 14/415 (SYSOP)
gupta@asgb.UUCP (Yogesh K Gupta) (11/06/85)
In article <10852@ucbvax.BERKELEY.EDU> c160-3ay@ucbzooey.BERKELEY.EDU (Banquo's Ghost) writes: >Subject: infinitesimal bees >Newsgroups: net.puzzle > >Here's one from a highschool physics class: > >At time 0, two cars are 5 miles apart, headed directly towards each >other, each moving at 20 miles per hour. (The speed remains constant >throughout the problem.) > >At time 0, a fast bee flies from one car towards the other. As soon >as it reaches the other car, it turns around in infinitesimal time >and heads back towards the first car. And so on. This bee flies at >30 miles per hour. > >How far does the bee travel before being demolished in the eventual >collision? > >...Ranjit As the two cars are 5 miles apart, and are moving towards each other at 40 miles/hour, the collision will occur in 5/40 or 1/8th hour. The bee would have travelled 30* 1/8 or 3.75 miles by then. ps. There is a story that goes with this problem. When posed to a genius (I do not remember the name), he replied after a short pause, "3.75 miles". The person who had posed the problem then said, "I expected you to do the mathematical series." To which the reply was, "I did." Yogesh Gupta. -- Yogesh Gupta Advanced Systems Group, {sdcrdcf, sdcsvax}!bmcg!asgb!gupta Burroughs Corp., Boulder, CO. -------------------------------------------------------------------- All opinions contained in this message are my own and do not reflect those of my employer or the plant on my desk.
ins_akaa@jhunix.UUCP (Kenneth Adam Arromdee) (11/06/85)
In article <10886@ucbvax.BERKELEY.EDU> c160-3ay@ucbzooey.UUCP (The Grinch) writes: >Alright then, what common english word is invariant under the alphabet >transformation of A-Z, B-Y, C-X, etc.? Obviously no word can transform into itself, because then every letter in it would have to transform into itself, and no letter does. However, WIZARD transforms into DRAZIW which is its own reversal. -- ------------------------------------------------------------------- If you know the alphabet up to 'k', you can teach it up to 'k'. Kenneth Arromdee BITNET: G46I4701 at JHUVM and INS_AKAA at JHUVMS CSNET: ins_akaa@jhunix.CSNET ARPA: ins_akaa%jhunix@hopkins.ARPA UUCP: ...{decvax,ihnp4,allegra}!seismo!umcp-cs!aplvax!aplcen!jhunix!ins_akaa