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I'll take a shot at this, although I bet others will correct me.  This is
purely for theoretical reasons, since your best bet is to just visit a
museum with your wind speed gauge handy. Or buy a blower with a variable
speed control.

Take a look at this webpage on terminal velocity, since you are essentially
achieving static equilibrium by matching the force of gravity with the force
of air resistance.  Too fast a blower and the ball will hover too far away
and won't have a stable enough air stream to find it's equilibrium
velocity.  Too low and it cannot compete against gravity.  Make sure you buy
a blower with speed control.  I'm sure the archives will have
recommendations.  Then just pick a heavier or lighter ball if needed.

As for blower cross-section, I would assume the larger the better since you
are trying to achieve the most air buffer possible around the ball, while
still maintaining your wind speed.  I'd be curious what others have found.

-Eric

Jeff Courtman <[log in to unmask]> wrote:

> I'm sure there are folks out there that have already taken a stab at this,
> but didn't find anything in the archives:
>


> For instance, if I know the weight of the ball and the diameter, is there
> an easy (reasonably) way to get in the ballpark with regard to air delivery,
> size of the air column, amount of lift, etc......?  Or am I just walking
> down a primrose path?
>
>
>
>
>
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