Aussie wrote on Feb 2
nd, 2009 at 9:13am:
Thanks for posting the link. Thanks especially to Luis for offering his services as it gives a lot of credibility to the segment to see a genuine slinger demonstrate his skill.
Strange how they were looking for a striking force rather than an energy or even momentum figure. Most ballistics tables for firearms stress energy as "striking force" is very dependent on the nature of the object being struck. For example cricketers or baseballers will easily absorb the impact of a catch as their hands move back even an inch or so. The same ball if striking their heads would cause serious injury or death. The collision takes place over a shorter time so the force is inversely greater, a phenomenon known as the impulse of the force.
Pity they didn't chronograph and weigh the stone. It would have been nice to know how fast and how heavy it was to compare with my/our own capabilities. They comment on the fact that the tail of the release cord "beaks the sound barrier" which actually has no bearing on the speed of the stone which has well and truly exited the pouch by that time anyway.
Still much more objective than the run of the mill DvG type presentations where they can't quite decide if they think the encounter was a "miracle" or not and lob for a sort of non-miraculous miracle stance.
I agree with a lot of your reservations, Aussie, but on the positive side - this is the first example as far as I know where a program researcher actually contacted this Forum to actually seek advice, and I think we might take it that the responses had a positive effect.
There were certainly some tiresome aspects of the program, and like you I would take some exception to some of the 'physics' arguments (not withstanding the appearance of various academics!) but I suppose I'm resigned nowadays to the production values of such programs being more tightly controlled by 'entertainment' rather than solid closely argued discussion, which has low market appeal nowadays.
The makers of these programs are (unfortunately!) not making them for those few of us who eagerly await every detail to be gleaned. I think the constraints often mean that the contributions of experts are not really done justice either.
This program at least did an outstanding job of showing a modern expert slinger doing something tremendously impressive. I think that is something to treasure!