Re: [Phys-l] football orientation in flight

["Pete Lohstreter" <plohstreter@MAIL.HOCKADAY.ORG>]

Forum for Physics Educators <phys-l@carnot.physics.buffalo.edu> writes:
> Here's a question I got from one of my students that I would appreciate
> your input on:  Why does a football, in the case of a long pass, tip
> over during the course of its flight so that it is always pointing, to
> at least a pretty good approximation, in the direction of its velocity,

Smallest cross sectional area is along the long axis of the ball.  As it
decends, aerodynamic forces are at a minimum if the orientation is along
the long axis of the ball.  I suspect that this would not be the case on
the moon.

There is a small effect of angular momentum if the ball is set into a
spiral motion.  The effect of tilting over will cause the long axis to be
'torqued' to the right (or left depending on the direction of the spiral)
a few degrees.  





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