Serious Scientific Answers to Absurd Hypothetical questions

[sevenperforce]

10 hours ago, MaverickSawyer said:

I've always kept an eye on a polymer-backed ceramic tile array for superior armor protection. Think of composite armor on a tank, but on a smaller scale. Three layers of tesselated hexagonal tiles, staggered in a triangular pattern, with each layer separated/bound/encased by a kevlar-impregnated rubber, backed by a kevlar spall layer. I'm not sure how much more effective it'd be than existing AR-500 steel plates backed by kevlar, or if it'd be lighter, but it'd possibly be more flexible than the steel plate setup. Not sure if it'd be worth the tradeoff of possibly reduced protection. And the major downside of the ceramic tile concept compared to the steel plate system would be a noticeable reduction in protection if hit on the same tile as a previous shot, though.

Sounds like dragonskin body armor. They made quite a bit deal of out it a few years ago. IIRC it degraded really quickly under high temperature fluctuations and couldn't handle grit or sand. May also have had a shrapnel effect with multiple hits to the same area -- i.e., plate fragmentation would end up sending ceramic shards through the inner lining if you got hit more than once.

[Gargamel]

Ignoring the fact that it would get destroyed by the firing of the bullet...   If we were to glue a fly to the back side of a larger caliber super/hyper-sonic bullet, would the fly survive until landing?  Would the low pressure zone behind the bullet keep it safe and tidy? 

*Bringing this thread back on topic* 

[MinimumSky5]

How long is the bullet in the air for?

That low pressure zone may get so rarefied, that the fly would suffocate before the bullet impacted the target.

[Mad Rocket Scientist]

My guess is that the g-forces from deceleration due to the air would kill the fly. 

A quick bit of searching found this page: http://www.dexadine.com/bexhelp/bexhelp116.htm

Which has this graph:

I believe the lines are based on models of different shapes of bullets, which wikipedia has some more info on: https://en.wikipedia.org/wiki/External_ballistics#Fixed_drag_curve_models_generated_for_standard-shaped_projectiles

The only thing I could find on insect g-tolerances was this: http://www.sciencefocus.com/qa/whats-highest-g-force-insect-can-survive

So it looks like hypersonic bullets of certain shapes decelerate fast enough to kill a bug. Of course there's probably quite a bit of shock heating at mach 5.

[K^2]

That really raises an important question. What is the G-tolerance of a common fly? I would imagine it to be pretty high.

Low pressure in the wake won't be a problem, though. Flies are pretty resilient to near vacuum. Video behind spoiler tag.

Spoiler

 

 

[Mad Rocket Scientist]

20 minutes ago, K^2 said:

That really raises an important question. What is the G-tolerance of a common fly? I would imagine it to be pretty high.

Low pressure in the wake won't be a problem, though. Flies are pretty resilient to near vacuum. Video behind spoiler tag.

  Hide contents

 

 

So how do flies get oxygen into their bloodstreams without lungs? Do flies even have blood? I don't know anything about flies.

[Green Baron]

18 minutes ago, Mad Rocket Scientist said:

So how do flies get oxygen into their bloodstreams without lungs? Do flies even have blood? I don't know anything about flies.

Search spell: Tracheal breathing. Very simple and much less effective than lungs. Insect size can be linked to atmospheric oxygen level in earth history. But tracheal breathing in connection with the material chitin limits the size of such animals on land and in the air as the gravity would crush them.

Blood ? I should know but i am insecure. You'll surely find out :-)

Edited August 19, 2018 by Green Baron

[Gargamel]

2 hours ago, K^2 said:

That really raises an important question. What is the G-tolerance of a common fly? I would imagine it to be pretty high.

I would think so.  You swat one out of the air with a fly swatter, crashing it to the ground, and it gets up and flies away. 

[kerbiloid]

Cockroaches survived 300 g in a centrifuge.

[MaverickSawyer]

And yet, I hit a wasp with my hat in midair today, and it didn't get back up. o.O

[Xd the great]

21 minutes ago, MaverickSawyer said:

And yet, I hit a wasp with my hat in midair today, and it didn't get back up. o.O

You squashed it?

G tolerance is almost proportional to body size, so the smaller you are, the tougher you are.

[kerbiloid]

1 hour ago, MaverickSawyer said:

I hit a wasp with my hat in midair today

Mr. Kung Lao? 

Spoiler

_{Upd: Not sure if "sensei" as not Japanese character.}

57 minutes ago, Xd the great said:

You squashed it?

Cut into halves.

Edited August 20, 2018 by kerbiloid

[Green Baron]

4 hours ago, kerbiloid said:

Cockroaches survived 300 g in a centrifuge.

Really ?

[kerbiloid]

6 minutes ago, Green Baron said:

Really ?

From a paper book. Personally haven't tried.

P.S.
Logically, why not. A cockroach is ~0.5 cm thick, a human is ~25 cm thick.
So hydrostatic pressure is 50 times less.

Edited August 20, 2018 by kerbiloid

[magnemoe]

12 hours ago, Mad Rocket Scientist said:

My guess is that the g-forces from deceleration due to the air would kill the fly. 

A quick bit of searching found this page: http://www.dexadine.com/bexhelp/bexhelp116.htm

Which has this graph:

I believe the lines are based on models of different shapes of bullets, which wikipedia has some more info on: https://en.wikipedia.org/wiki/External_ballistics#Fixed_drag_curve_models_generated_for_standard-shaped_projectiles

The only thing I could find on insect g-tolerances was this: http://www.sciencefocus.com/qa/whats-highest-g-force-insect-can-survive

So it looks like hypersonic bullets of certain shapes decelerate fast enough to kill a bug. Of course there's probably quite a bit of shock heating at mach 5.

Amazing how much the boat tail help, note that mach 3 is fast for bullets. 
Only thing who goes significantly faster is discarding sabot from tank guns who is even more streamlined. The G1 profile is more for pistol bullets 

Bring up another amazing tidbit. US navy looked at the best way to shooting long range artillery with smart shells like the current gps guided one. 
They found the best way was to shoot it straight up and then angle towards target high up in the air to reduce drag so you could have an gun who was fixed like that. 
it would be far lighter than an gun turret. 
Downside is that you could only use it for long range with smart shells, not standard shells nor closer ranges. 

[Green Baron]

1 hour ago, kerbiloid said:

From a paper book. Personally haven't tried.

P.S.
Logically, why not. A cockroach is ~0.5 cm thick, a human is ~25 cm thick.
So hydrostatic pressure is 50 times less.

I am not saying "impossible", but afaik a swat with a fly flap is in that range 2-300g or so and most flies don't recover from that if you don't give them a chance ;-) But a continuous g load is something different than a shock load, the latter being easier to endure for insects as well as vertebrates.

A cockroach is much more fragile than one might think. The males here are in the range of 3-5 centimeters and weigh maybe 3-5 grams. 300g would definitely damage or even flat them out. I have a 500gr hammer here, i can try on the carcass of the next one i kill, but i know the outcome (i will have to clean up ;-))

Anyway, the walls of the trachea aren't made for this, they collapse under load, cutting off the oxygen supply. That is one size limiting factor for insects.

Edited August 20, 2018 by Green Baron

[kerbiloid]

OK.

http://www.astronaut.ru/bookcase/books/gerd/text/10.htm

Tsiolkovskiy's experiments:
cockroaches 300 g
chickens 10 g

Further experiments:
insects - 2000 g
frogs - 50 g
cats - 20 g _{Blasphemy. But maybe those were volunteer cats. Otherwise that's one more human crime.}
dogs - 80 g * 5 min

Upd.
https://dxdy.ru/topic25943-15.html

Dogs:
80 g - 2 min
40 g - 5 min
98 g * 5 min = death for anemia, but without bowel rupturing.

Upd.2

http://forums.balancer.ru/tech/forum/2004/01/t24178--maksimal-dopust-peregruzki-g-na-zhivoj-organizm.html

Settling (?)  bacteria from a solution - 10 000 g.

Tortoises returning from the Moon - aerobroke at 20 g and stayed fine.

 

2 hours ago, Green Baron said:

cutting off the oxygen supply.

Did you try to drown an insect or a spider?

Edited August 20, 2018 by kerbiloid

[KG3]

13 hours ago, Green Baron said:

Search spell: Tracheal breathing. Very simple and much less effective than lungs. Insect size can be linked to atmospheric oxygen level in earth history. But tracheal breathing in connection with the material chitin limits the size of such animals on land and in the air as the gravity would crush them.

Blood ? I should know but i am insecure. You'll surely find out :-)

Insects use hemolymph instead of blood.  They employ an open circulatory system instead of arteries and veins, which means that the hemolymph just kind of sloshes around inside the exoskeleton.  The trachea are basically just a bunch of tubes that deliver air into the body of the insect.  

https://en.wikipedia.org/wiki/Insect

  "Late Carboniferous and Early Permian insect orders include both extant groups, their stem groups,[27] and a number of Paleozoic groups, now extinct. During this era, some giant dragonfly-like forms reached wingspans of 55 to 70 cm (22 to 28 in), making them far larger than any living insect. This gigantism may have been due to higher atmospheric oxygen levels that allowed increased respiratory efficiency relative to today"

If you want to see some amazing adaptations look into aquatic insects.  They have come up with some really wild solutions to living in this environment.  I could go on and on...

[Green Baron]

I know that, i have written about it several times here. I just did not want to write it over and again, because of that i just gave the search term. And, in all friendship, i feel bothered when Wikipedia is cited before me.

But, of course, i am always happy if somebody else finds out ;-)

hemo- = blood-, but i am insecure where a line is drawn, it is surely not only a lack of red blood cells like in vertebrates. That i don't know.

Edited August 20, 2018 by Green Baron

[MaverickSawyer]

10 hours ago, Xd the great said:

You squashed it?

G tolerance is almost proportional to body size, so the smaller you are, the tougher you are.

Kinda. More of a beat-down. It wasn't squashed, but it certainly didn't take off again afterwards.

That said, I usually prefer to tase wasps. Harbor Freight sells electric fly swatters for cheap, and they work perfectly fine.

[MinimumSky5]

1 hour ago, Green Baron said:

hemo- = blood-, but i am insecure where a line is drawn, it is surely not only a lack of red blood cells like in vertebrates. That i don't know.

No, insects don't have red blood cells, and only a few have any oxygen carrying pigments in their blood. Those that do have it simply dissolved throughout the hemolymph.

[Green Baron]

Yeah, that too is what i meant with the "not only a lack of red blood cells".

I am hard to understand apparently :-)

Edited August 20, 2018 by Green Baron

[Gargamel]

13 hours ago, Green Baron said:

I have a 500gr hammer here,

That's not a g load, that's a traumatic crush injury. 

12 hours ago, kerbiloid said:

Tortoises returning from the Moon - aerobroke at 20 g and stayed fine.

WAIT!!    What?   When did we send turtles to the moon?

8 hours ago, MaverickSawyer said:

That said, I usually prefer to tase wasps. Harbor Freight sells electric fly swatters for cheap, and they work perfectly fine.

Buy a second one, give to a friend, and joust.   Loads of fun. 

[TeslaPenguin1]

How many saturn V's, placed at the equator, would it take to stop the earth's spin?

How many would it take to crash the moon into earth?

[kerbiloid]

4 hours ago, Gargamel said:

When did we send turtles to the moon?

Not turtles but tortoises! _{Just a lol, as in my language this is the same word.}

In 1968, Zond-5.
Two Soviet tortoises (and various invertebrates) were the first Earth beings ever sent to another celestial body (and successfully returned back).
Of course, it was a fly-by, not landing.
3 months later Apollo-8 repeated this with three mammals.