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Plank in a corridor

Plank in a corridor

Posers and Puzzles

talzamir
Art, not a Toil

60.13N / 25.01E

Joined
19 Sep 11
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59278
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31 Oct 11
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A straight wooden plank that doesn't bend at all is carried in a long that is 10 feet wide and seven feet high. At one point there is a T-crossing to a side passage five feet wide. How long can the plank be if it makes it through the crossing?

s
Fast and Curious

slatington, pa, usa

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28 Dec 04
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53321
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01 Nov 11
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Originally posted by talzamir
A straight wooden plank that doesn't bend at all is carried in a long that is 10 feet wide and seven feet high. At one point there is a T-crossing to a side passage five feet wide. How long can the plank be if it makes it through the crossing?
Looks like 2 triangles 10x5 with the board being the length of the hypotenuse times two, or the square root of 125 times two= 22 feet and change. That would be if the board was carried in two dimensional space. I think the third dimension of 7 feet high, btw, the 5 foot wide corridor had an unspecified height so going by the exact wording, you can't strictly use the height so would have to treat it as a two dimensional passage.

talzamir
Art, not a Toil

60.13N / 25.01E

Joined
19 Sep 11
Moves
59278
Clock
01 Nov 11
1 edit
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Ah, sorry. This makes three variants:

a. The side corridor is as high as the main corridor.
b. The side corridor is extremely high.
c. The side corridor has a generic height h that will remain as a parameter to the plank length.

a. is as I had at first intended it but the others can be interesting too.

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