Free falling spinning rectangle

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SUMMARY

The discussion centers on the dynamics of a free-falling rectangular piece of paper that spins about its longitudinal axis, which results in a longer descent time compared to other shapes. This phenomenon occurs due to the paper's orientation, which minimizes air resistance when edge-on to the airflow. Additionally, the feasibility of generating electricity from a free-falling propeller is explored, with the conclusion that while it is possible, the initial conditions of the fall and air dynamics play crucial roles in the effectiveness of power generation.

PREREQUISITES
  • Understanding of basic physics principles, particularly dynamics and aerodynamics.
  • Familiarity with concepts of air resistance and drag forces.
  • Knowledge of energy generation methods, specifically from kinetic energy.
  • Basic understanding of rotational motion and its effects on falling objects.
NEXT STEPS
  • Research the principles of aerodynamics related to different shapes and their fall dynamics.
  • Explore methods for calculating air resistance and drag on various objects.
  • Investigate energy harvesting techniques from kinetic energy, particularly in free-fall scenarios.
  • Learn about the design and efficiency of small-scale wind turbines or propellers for energy generation.
USEFUL FOR

This discussion is beneficial for physicists, engineers, and hobbyists interested in aerodynamics, energy generation, and the physics of falling objects.

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 resistance 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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