Re: [Phys-l] Science show "Humanly Impossible" on National Geographic channel.

[Brian Whatcott <betwys1@sbcglobal.net>]

David asks if the movie makers will get the science right.

So it is instructive to ask if the science teachers will get the science 
right too...

Take the visual acuity thing.
This is a very old design - shared by creatures with bilateral symmetry
on a backbone - and some others with neither feature.
With old designs that have seen continual development - a certain 
caution is wise: acuity could be a function of limiting aperture, of 
focus aberrations,
of focal plane geometry, of sensor variable sensitivity, of spectral range
and so on.   So it is a mix of factors, one of which is the switch from 
low light rod vision in the periphery to cone vision in the central 
focal area as the light grasp increases.

 Body suspension sounds intriguing - brings to mind an old pilots' game 
- two really.
Take three chairs in line: the contestant lies along the three chairs, 
then the central one is removed. This is easier than it looks. More 
impressive is suspension between two seat BACKS. The muscular strength 
is not excessive - but the pressure point at the neck needs padding.

Another: draw a line on the floor: contestants walk out two beer bottles
until they can leave one on a far (high-water) mark. The imagination is 
the principal enemy here: better not to think about a bottle breaking at 
the neck - though it has happened.

Fire-walking has certainly received the best science reviews in recent 
years - seeing several people walk a line- then seeing another getting 
burnt when running  it is instructive (Mythbusters).

I found the man vs car setup amusing.
That a handler should want to weaken the clutch makes sense to me.
Although a steam loco can develop impressive standing thrust,
an auto needs slow speed and smooth clutch engagement for preference
because its starting thrust is low - but still enough to snatch a man 
off his feet without a little sleight of hand....

What's the science involved in sword-swallowing? A matter of a
comformable gullet upper digestive system and practice, as it seems to 
me. There are numerous stories of such performers  collection 
lacerations or remnant left-overs inside....

Brian W

David Willey wrote:
> In January of 2009 I worked for the Atlas Media Company filming the 
> pilot of a reality science program, “Humanly Impossible”, for the 
> National Geographic Channel. My part was to explain the science, 
> primarily the physics, behind four of the eight activities highlighted 
> in the show. Namely, fire-walking, body suspension, sword swallowing and 
> a strongman holding back a car.
>
> I was assured at the time that every effort would be made to “get the 
> science right” and it did seem to me, during the filming, that this was 
> indeed one of the director’s goals. My opinions and advice were 
> solicited and as far as I could tell, were taken into consideration. 
> It’s hard to tell with media people though.
>
> Atlas Media just informed me that the shows (there are actually two of 
> them, each an hour long) are going to first air on the National 
> Geographic channel on Sunday, December 6^th , 2009 at 8pm and 9 pm, 
> Eastern time. They are to be repeated later that week. A preview and the 
> option to be reminded by email when the shows air, are available at:
>
> http://channel.nationalgeographic.com/series/humanly-impossible/all/Overview
>
> I’m going to be very interested to see how well the promise of “getting 
> the science right” is kept. I know some others of you have not had good 
> experiences with the media. From what I saw the body suspension was the 
> most “real” activity, with nothing faked; the strongman however seemed 
> to be somewhat of a sham. The segment was filmed twice, as the 
> strongman’s driver burnt the car’s clutch out within ten minutes of the 
> car arriving. I was only present for this first ten minute part. At the 
> time I voiced the opinion that it doesn’t matter how strong the man is, 
> with regards to him being dragged across the floor, that it is more a 
> question of the size of the coefficient of friction and the man’s 
> weight, as the strap, supposedly holding him back, never went taut (see 
> the preview video.) I was not present for the majority of this segment, 
> although the way the clip appears to be edited, you’d think I was there 
> for the whole test. /snip/
> David