Re: [Phys-l] An intersting integral calc. problem.

[brian whatcott <betwys1@sbcglobal.net>]

 On 7/10/2010 10:14 AM, Pete Lohstreter wrote:
> *betwys1@sbcglobal.net <mailto:betwys1@sbcglobal.net> writes:*
>  Good question.
> It parses two ways:
> real ball?
> real golf ball?
>
> There is always the possibility of massaging an image via a finite
> element package.   Though real golf balls vary, this image seems to 
> depict something out of the useful range: an experimental
>  ball of such high fluidity and low coefficient of restitution
> would be  all but useless for golf, one supposes.

> Photoshop and a water balloon would look the same as the vid.  Just a 
> thought.
>
> Pete Lohstreter
I wondered about that.   "Photoshop" is a word rapidly gaining generic 
portmanteau status like Hoover, Xerox etc. for lifelike digital graphic 
image distortions.
Producing convincing images of spherical vibrations from a shock excited 
sphere  is not easy.   Slow motion of a water balloon dropped on a 
plate, with its surface texturized and the umbilical removed might work, 
I can see.

Finite element methods can also  do a  convincing job.
Here's an amusing (?)  example from a Chinese University:
the vibrations of a pear.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1473996/

Other workers have done vibration analyses of pineapples, apples etc., 
etc.  But as I have probably mentioned before, the most striking 
research results  that I recall, concerned the spherical vibrations of 
the Sun, a work carried out  by a Franco-American collaboration using 
interferometric methods on the  hyperfine Solar sodium lines to deduce 
integrated breathing mode velocities of the Solar surface in the 
meters/second range...

Brian W