[net.math] Largest 2-d object around 90-degree corner?

bundy@oasys.UUCP (12/12/85)

We all remember the old first semester calculus question asking what
is the longest board (i.e. 1-dimensional rigid body) that can fit
around a 90 degree turn between two corridors.  What is the biggest
two dimensional rigid body that can fit around the turn and can also
slide freely down both corridors:

______________________________
                             I
                             I
                             I
_________________            I
                 I           I
                 I           I
                 I           I
                 I           I
                 I           I
                 I           I
                 I           I
                 I           I
   

Both corridors are infinite length, width a, and we are interested in
the 2-d rigid body of greatest area that goes around the corner.  
Certainly the square of width a fits, but a little thought will reveal
shapes of significantly greater area.

-- 


Bruce Bundy

{ucbvax,hao,allegra}!nbires!oasys!bundy

jankok@zuring.UUCP (Jan Kok) (12/16/85)

In article <167@oasys.UUCP> bundy@oasys.UUCP writes:
>. . . .  What is the biggest
>two dimensional rigid body that can fit around the turn and can also
>slide freely down both corridors:
> . . . 
I have seen the problem been posed about 15 years ago
by Hammersley in a British journal.
The solution method is elementary and I won't spoil it for you.
-- 
jan kok, cwi (afd. nw), amsterdam, nederland
UUCP: {seismo, decvax, philabs, okstate, garfield}!mcvax!zuring!jankok
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