Free falling spinning rectangle

AI Thread Summary
A rectangular piece of paper spins as it falls, taking longer to reach the ground compared to other shapes due to its orientation and air resistance dynamics. The spinning motion is influenced by initial fall conditions, air streams, and the paper's lack of symmetry. There is potential to generate electricity from a free-falling propeller, although practical implementation would require consideration of the energy needed to lift it initially. The discussion highlights the complexities of aerodynamics and energy generation in free fall scenarios. Overall, the feasibility of using a falling propeller for practical purposes remains a topic of interest.
kurious
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A rectangular piece of paper spins rapidly about its longitudinal axis as it falls
through the air.It takes longer to reach the ground than other shapes of paper.Why is this given that it spends a lot of time edge on to the flow of air and so encounters less resistance from the air than a surface of constant horizontal orientation?
And could I generate enough electricity from a free falling propeller to do something useful with - even if it's only going to turn on a light so I can read a book as I parachute from a plane at 2 in the morning.
 
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I don't know what you meant about air resistence and stuff,
but I figure that the spinning part depends on start conditions
of the fall, air streams, and lack of symmetry.

As for generating power from a falling propeller, of course
it could be done. But remember the saying (in reveres though ;) ):
what comes down must first go up. :biggrin:

Live long and prosper.
 
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