[Bored chemist]

Stapp discovered that the product pretty well determines the damage to a bag of giblets in jelly

Did you read my post?

Do you really think that the effect on the rider's body of stopping a sledge from 100 m/s in 1 second is the same as doing it in 100 seconds?

[Bored chemist]

100 stapp of deceleration, however delivered, tends to separate the entrails though it is survivable if you are sitting backwards.

OK We can arrange that by accelerating for 0.1g for 1000 seconds.
I think that's about what you would expect if you spent 15 to 20 minutes on a merry-go-round.
Would that do you any harm?

[alancalverd]

Do you really think that the effect on the rider's body of stopping a sledge from 100 m/s in 1 second is the same as doing it in 100 seconds?

So here's the problem.

It is obvious that the body can sustain a lot of acceleration - say 100g -  for a short time compared with the propagation time of an impulse across the body, but not for a long time as bits become detached or crushed depending on the sign of the acceleration.  So the product of time x acceleration is an important parameter of harm. But as you say there is a threshold acceleration (probably around 2 - 3g) below which no harm seems evident however long it is sustained for.

So the graph of shock vs harm is actually a 3D surface rather than a simple curve.  No problem. 

[Bored chemist]

Once you recognise that the "shock" isn't the only thing, and you need to consider the duration (twice) it's not clear that it is any advantage over a 3D surface of "harm" vs acceleration and time.
For things other than crashes, the frequency of vibration is also important.

But the tortoise still gets something like 1000 G.

[alancalverd]

But the tortoise still gets something like 1000 G.

Really? What planet does he live on? What units of mass and length do they use? Terrestrial tortoises only get multiples of g.

Did you really calculate the terminal speed of a tortoise in air? What value did you get? (2 mph seems to be the horizontal limit, not determined entirely by air drag)

[Bored chemist]

(2 mph seems to be the horizontal limit, not determined entirely by air drag)

Really, on what planet?
Here on Earth, the record seems to be
0.28 m/s
Equivalent to about 0.6 mph.


https://www.guinnessworldrecords.com/world-records/77951-fastest-tortoise

Did you really calculate the terminal speed of a tortoise in air? What value did you get?

Of course I didn't.
I googled it.
https://casualcalculations.wordpress.com/2013/04/18/the-tortoise-and-the-hare/
... the terminal velocity of the tortoise is about 80 metres per second...

But all I did with that figure was to eyeball it and confirm "it's probably enough".

I calculated the acceleration the easy way.

[Just thinking]

A cockroach in a rifle barrel.

[syhprum]

I would not expect the tortoise to suffer more than 50 g it depends on the hardness of its shell and that of the rock.

[syhprum]

The sledge accelerating experiments were interesting as for a short time they resulted in the highest speed any human had travelled (about 1000 mph) , the vehicle was accelerated by a rocket engine and slowed by a water brake.
Racing drivers occasionally suffer 50g acceleration if they run into Tyre barriers but live to tell the tale.   

[Bored chemist]

I would not expect the tortoise to suffer more than 50 g it depends on the hardness of its shell and that of the rock.

My calculation was based on about 10 metres (or more) and about 10 mm.
What figures did you use?

[Just thinking]

I know I've got it this time the Roadrunner I remember seeing it on TV.

[Zer0 (OP)]

Correct Option - None of the Above.
👍


Are the following figures roughly approximately somewhat accurate?
(Incredible?)

" A tiny reptile called the rosette-nosed chameleon holds the current record among the amniotes: that is, animals that give birth on land, meaning reptiles, birds and mammals. It can flick out its tongue so rapidly that it briefly accelerates at 2,590m/s/s - about 170 times faster than the 15m/s/s maximum acceleration of the cheetah or the peregrine falcon. "

" Those first measurements, taken at 5,000 frames per second, showed that peacock mantis shrimps could accelerate their clubs at an eye-popping 104,000m/s/s; comfortably 20 times as fast as any amphibian or reptile. "

"However, it is not clear whether or not this "you have to be slow to be fast" idea plays out in all circumstance. Impressive though they are, the 1,000,000m/s/s accelerations achieved by trap-jaw ants are no longer world-beating.

Their record has been blown out of the water by the humble jellyfish. "

" When the cell is triggered and that elastic energy is released, a microscopic harpoon-like structure shoots out of the nematocyst. The harpoon can reach peak accelerations of about 50,000,000m/s/s: 50 times the peak trap-jaw ant acceleration. "



Source of Information -
http://www.bbc.com/earth/story/20160916-how-some-animals-accelerate-faster-than-all-others

Note - Link is Http!

P.S. - Thanks All for Participating.
😇

[Just thinking]

That leaves my dog running to his food boll out of the race.