Path: utzoo!utgpu!attcan!uunet!steinmetz!vdsvax!thearlin
From: thearlin@vdsvax.steinmetz.ge.com (Kurt Thearling)
Newsgroups: sci.electronics
Subject: Re: WHat are those holes for?
Message-ID: <4966@vdsvax.steinmetz.ge.com>
Date: 28 Jul 88 16:34:53 GMT
References: <10790@oberon.USC.EDU> <327@richp1.UUCP> <303@btree.uucp> <1550@tekirl.TEK.COM> <134@ai.etl.army.mil>
Reply-To: vdsvax!thearlin@steinmetz.UUCP (Kurt Thearling)
Organization: General Electric CRD, Schenectady, NY
Lines: 34

In article <134@ai.etl.army.mil> richr@ai.etl.army.mil (Richard Rosenthal) writes:
>Re: Man Hole Covers
>
>Triangular (3 sided) covers cannot fall through the hole.
>

this is incorrect.  using the following figure, it is easy to see that
the length AC is shorter than the length AB.  thus, if the manhole
were held such that AC were parallel to the ground, the manhole could
be dropped through the hole along AB. 

   
               A
              /|\
             / | \
            /  |  \       Note: not drawn to scale.  all sides are
           /   |   \            assumed to be the same length (i.e.,
          /    |    \           AB = AC = BD).  also assume that 
         /     |     \          BC = CD.
         -------------
        B      C      D


kurt

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Kurt Thearling                        thearlin%vdsvax.tcpip@ge-crd.arpa 
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