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Topic: Fly problem, alternative solution?
Replies: 6   Last Post: Oct 15, 2003 4:05 PM

 Messages: [ Previous | Next ]
 de Valmont Posts: 23 Registered: 12/12/04
Re: Fly problem, alternative solution?
Posted: Feb 8, 1997 2:30 PM

> Sure. I'll set the problem up, and you can finish it.
> Pick one of the trains as you reference point, and draw
> the graphs T(t), and f(t). T(t) is the train's distance from you
> versus time, and f(t) is the fly's versus time. Find the distance
> the fly travels in the first cycle, from your train to the other
> and back to you, call it D1. Because of the constant speeds in
> the problem, the graphs of T(t) is a negative-sloped line from
> (0,T(0)) to (tf,0). The graph of f(t) is an infinite series
> of similar triangles. From the parameters of the problem you can
> find a proportionality constant that relates
> the distance of the second cycle, D2, to D1. D2=cD1.
> So the total distance the fly travels is sum(n=1,oo)D1*c^n.

Yes, I have managed to solve it. It is simple:

s1*SUM(C^n,n=1,oo) where C = V1/V2 (If you have one train as a refernece
point)

//Luka
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mailto:devalmont@geocities.com
http://www.geocities.com/CapeCanaveral/1630/
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Date Subject Author
2/6/97 de Valmont
2/6/97 Jim Hunter
2/8/97 de Valmont
2/7/97 Ilias Kastanas
2/8/97 de Valmont
10/13/03 prem
10/15/03 A N Niel