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Re: [OM] IMG: The Red Carpet

Subject: Re: [OM] IMG: The Red Carpet
From: Jim Nichols <jhnichols@xxxxxxxxxxxxx>
Date: Thu, 29 Oct 2015 23:08:53 -0500
Hi Mike,

As a retired Aeronautical Engineer, I tend to notice the shapes of things that blow in the wind. The maple leaves, at least from this tree, are cambered slightly, with the red side having positive camber, and vice-versa, as seen in this image:
http://www.gallery.leica-users.org/v/OldNick/Leaf.TIFF.html

This should affect the tumbling during the falling path, but I am reluctant to offer a guess of the outcome. Height, wind, and other variables would also contribute.

I choose to enjoy the colorful sight, not ponder things that would cause me to lose the final few hairs on my head. :-) Thanks for looking.

Jim Nichols
Tullahoma, TN USA

On 10/29/2015 9:11 PM, Mike Gordon via olympus wrote:
        Fifty Fifty Moose and Chuck write:


On 10/28/2015 6:46 PM, Chuck Norcutt wrote:

<<Well, it surely seems that 1/2 of them have fallen bottom side up.

FFM:
<<<<Odd that, coins seem to do the same thing. :-)


Are you both really  so sure falling Sugar Maple leaves are statistically 
equivalent to tossing  a fair coin? Many aerodynamic and structural variables 
affect their falling one side up or the other,
but they all start in one orientation perhaps skewing the distribution. Haven't 
you observed some floating down in calm conditions remaining red side up? A 
stiff breeze would likely randomize the falling
but under calm conditions is it not reasonable to hypothesize a slight 
preponderance of the red side up?   So how to test:  Perhaps mark off a fixed 
area and  count all the leaves in each orientation.
  A back of the envelope 2X2 table  (df thus=1) would dictate a chi square of 
about 3.9  to assure p<0.05 testing for a 45/55 distribution vs 50/50.  That 
would take roughly 400 leaves.  Leaf morphology changes a bit with water 
availability and especially light and further changes with advancing cold.  How 
that affects aerodynamics and tumbling, I don't know.

http://www.sciencedirect.com/science/article/pii/S1002007109003013


I can see this morphing into a Ph.D. thesis or better yet a project for a kid 
or grand kid.

Fifty-five, forty-five, Mike



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