Re: [Phys-L] Water Slide Video & drag force

[bernard cleyet <bernard@cleyet.org>]

While JD is away, I’ll try my dime (inflation). 


Yup, poorly done.   Tibia/fib. partially out of the water presenting a more streamlined figure. (feet completely part of the time)

 My impression of the race car is backwards.  I thought often most of the drag is from the rear.  A blunt front and tapered rear is much better than the reverse.  (Vide the trout, also under navy ships.)  


bc awaits JD’s analysis.

p.s.  Some big rigs have plates mounted on the rear, so it presents a pyramid instead of the usual vertical flat plate.  

> On 2019/Aug/13, at 13:16, Folkerts, Timothy J <FolkertsT@bartonccc.edu> wrote:
>
>
> His model seems to more or less be treating a foot as having a mass of ~ 50 kg and estimating how those disembodied feet behave.  I can see that working reasonably well, but it seems an odd perspective for explaining the effect (especially since in the video, the pointed feet are pretty much completely out of the water and all of the drag from the water would be due to the legs and torso).