Re: [Phys-L] Dirigible Flight Question

[Paul Nord <paul.nord@valpo.edu>]

Ok, ok.  I'll give you the real question.  We've gotten bogged down in dirigibles and blimps.

I have altitude data for a weather balloon which picks up enough ice at a 5 km altitude that it begins to descend.  It continues dropping until it reaches about 2 km where enough ice has melted to allow the balloon to continue its ascent.  We know the lift of the balloon.  We know the mass of the payload.  What is the mass at the two points where the velocity goes to zero?

Paul


On Nov 5, 2012, at 4:56 PM, John Denker <jsd@av8n.com> wrote:

> On 11/05/2012 03:25 PM, Paul Nord wrote:
>
> > I'm really looking at the point where the velocity goes to zero.
>
> Well, if you are serious about the reeeeally low velocity case,
> that's been understood since 1851 ... more than fifty years before
> Kitty Hawk.  I'm not sure how low the local velocity can be, 
> experimentally, for a real dirigible, especially outdoors, but if 
> you're sure the zero-velocity limit is what you want ....
>
>   http://en.wikipedia.org/wiki/Stokes%27_law
>
> And yes, it's linear.
>
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