Useless Trivial facts
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Fraser
Active Member
The black marlin is known to be the fastest fish on the planet, with a top speed over 80km/h. But the real question (as always) is what if? What if you dropped a black marlin (point first) from a helicopter, from (say) 10,000 feet? With it's spear nose, heavy body weight and aerodynamic fins - could it break the sound barrier (1,236 km/h)? And would it leave a crater, or just (sort of) stick in the ground and wobble a bit. If so, could this be a useful way to BBQ (assuming it doesn't burn up completely on re-entry)? In today's uncertain times, these are the important questions we need to be asking ourselves!
Phil_Stacker
New Member
No. The fluid dynamics that leads to the speed is in large part due to the momentum generation within the viscous liquid. The black marlin is itself not "aerodynamic" but rather hydrodynamic with non-hydrodynamic stabalisation and momentum generating features.
Also, the centre of gravity in air is not the buoyancy centre of gravity, meaning that the fish won't stay head first just because you turn it that way. It is inherently unstable in aerodynamic structure and would likely spin on all planes, potentially stabalising, but even if it does its terminal velocity would not be great. Think of a large rock - once a meteor that is about the size of your fist, maybe 1-2kg in size slows down, it just drops and although it will hit your car with enough force to rip though some metal and it the ground, it won't leave a crater.
The marlin isn't hard, so its body will absorb much of the impact force and will splat outwards (i.e. Mythbusters used frozen and raw chickens with very big impact/penetration difference due to this effect).
Finally 10,000 feet isn't enough to "burn up". The heat generated is normally by compacted (compressed) air, not by friction with the air (a mistake very commonly made, even by some scientists). The marlin is very unlikely to compress so much air in front of it to cause even heating. Again, using that meteor example, you are more likely to get frost bite from a meteor if you pick it up straight away because the comprehensive heat is dissipated in the upper atmosphere, and then the material is exposed to very, very low temperatures. 10,000 feet wouldn't be super cold, but it isn't hot.
But give it a go and let me know what the results are?
Also, the centre of gravity in air is not the buoyancy centre of gravity, meaning that the fish won't stay head first just because you turn it that way. It is inherently unstable in aerodynamic structure and would likely spin on all planes, potentially stabalising, but even if it does its terminal velocity would not be great. Think of a large rock - once a meteor that is about the size of your fist, maybe 1-2kg in size slows down, it just drops and although it will hit your car with enough force to rip though some metal and it the ground, it won't leave a crater.
The marlin isn't hard, so its body will absorb much of the impact force and will splat outwards (i.e. Mythbusters used frozen and raw chickens with very big impact/penetration difference due to this effect).
Finally 10,000 feet isn't enough to "burn up". The heat generated is normally by compacted (compressed) air, not by friction with the air (a mistake very commonly made, even by some scientists). The marlin is very unlikely to compress so much air in front of it to cause even heating. Again, using that meteor example, you are more likely to get frost bite from a meteor if you pick it up straight away because the comprehensive heat is dissipated in the upper atmosphere, and then the material is exposed to very, very low temperatures. 10,000 feet wouldn't be super cold, but it isn't hot.
But give it a go and let me know what the results are?
Fraser
Active Member
While inclined to agree with you Phil_S, I'm not sure you can be that emphatic. Firstly (ignoring the coriolis force as a first approximation) wind resistance tends to align falling objects, so "point first" may in fact be the most stable orientation for a flying black marlin. The real point is this: I take offence at the peregrine falcon being labelled as the fastest animal on the planet (389 km/hr), without first recognizing the difference between air and water as a transportation medium. At least in my mind, the only true comparison is by match race in the SAME medium. In which case (correct me if I'm wrong) if you stick a falcon in a bucket of water then it is going nowhere and if you drop both from 10,000 feet then the marlin wins again. And if you consider the fastest land animal, the cheetah (100 km/h) then same job - hopeless at both swimming and flying! Yes I know that the black marlin (Istiompax indica) is known to struggle a bit on land, but hey, two outta three ain't bad!
Phil_Stacker
New Member
Fraser said:
Sorry this is false.
Wind resistance tends to align stable falling objects. An object that is unstable will not stabalise, or may (like some seeds of some trees) actually rotate. An object inherently unstable could rotate to the point it broke apart. So this "fact" is false. For instance, people tumble when they come out of a plane unless they are taught very precise movements to keep themselves stable.
That's why they put those little fins on rockets, because without them rockets kinda tumble. There are lots of examples, including your example of the falcon that has tail and wing stabilisation and other direction correction features, it's just a false statement assumption.
Assuming the marlin is living it is likely to move and any movement will immediately change aerodynamic stability. Unless you froze it exactly symmetrical (fins at the same width, perfectly aligned, it will tumble and will have a reduced terminal velocity.
Fraser said:
I take your point on the fastest animal by it's own momentum may not be the falcon, if the falcon is simply the fastest falling animal. But is an Albatross that glides for a km between flaps actually flying? It's not actively flapping, so it it not in flight? Is a turtle swimming if it is in a current and not using its flippers? It has speed - is that false speed?
But more to the point, I don't understand the argument about medium.
If you drop a falcon and marlin on the moon they both hit the ground out the same time. If you drop them both into water the falcon is likely to float (air in bones).
However, I would put money on a tightly compacted, low resistance (aerodynamic), highly stabalised falcon "falling" faster than any other animal. Even humans in a tight "pin drop" won't approach 389 km/hr (not that I've tried it).
So that means that the falcon, although technically falling (diving), would still have the highest terminal velocity of any animal, and given all speeds that all animals get to, must therefore be considered to get to the highest speed. It may not be flying the fastest, swimming the fastest, or the fastest on-land animal (or in land - don't forget the worms), but of all creatures on earth it is able to, at its will, get to the highest speeds.
So to me I don't understand the office you take.
Take a plane for example. You are going 200 kph, you turn off your engines, go into a dive, it hits 500kph - are you saying the plane isn't really going 500kph because it gained the speed through reducing altitude? Let's say that same plane can't go more than about 20kph on the ground, or about 5kph sink speed, then would you say the plane can't be considered as fast as my car because my car can go 150km/h on the land and can sink 15kph?
Phil_Stacker
New Member
Maybe you are after the "fastest in all mediums", which may (without setting up a race) be a flying possum that can burrow through soil, run, glide from tree to tree and can swim.
Fraser
Active Member
Your previous comment has flipped my switch. The fastest of all animals is US, good old homo sapiens (once we get off the couch). On land we can do 707 km/h (in a turbocharged Chevvy small bloc) and underwater we can do 370 km/hr (once placed in a Chinese supercavitation torpedo) and in the air we can do mach 2.35 (2,900 km/h) in any of the new Russian Sukhoi fighters. So I take it all back Phil - black marlins are losers!
Phil_Stacker
New Member
But if I have my dog with me.... it would also be the fastest.....
Fraser
Active Member
Soooo I was right after all - because if you drop a black marlin (nose first) from the back of a Russian Sukhoi whilst it is in a 2,900 km/h nose dive, then it would be the fastest animal on the planet, BECAUSE the falcon would just float around in there, the cheetah would probably grab hold of the pilot and start biting him and your dog would also be going nowhere, with its nose and one paw out the window... Argue that I'm wrong now smarty-pants - in fact don't, we're all getting bored now...
Phil_Stacker
New Member
Falling fact - a dime thrown from the empire state building is popularly believed to get to a speed it could kill someone. This isn't true (I'm sure it can hurt and do damage). But that's not the fun part. The empire state building has layers, and those layers are littered with dimes.
There are a lot of people who must like the idea of potentially killing strangers.
There are a lot of people who must like the idea of potentially killing strangers.
Barbie's measurements, if she were life size, would be 39-29-33
Phil_Stacker
New Member
If you google "realdoll" you can see the life-size doll.
Phil_Stacker said:
No thanks Phil_the pervert, I've got one coming for xmas don't wont to ruin the surprise
Phil_Stacker
New Member
They kinda freak me out. Saw a docco on it where these guys treated the dolls like real women.
Fraser
Active Member
Re: MASTERS closing down:
(1) I'm told the nit-wit CEO is being paid 4 million to step down, while thousands of shop floor workers are facing unemployment at Christmas!
(2) It's amazing what a 90% OFF sale does to the human mind. I bought $2,500 worth of crap that I don't need for just $250.
Did I save $2,250 or just lose $250?
If anyone needs 500 galvanized bolts (without washers or nuts), or 50 garden sprinklers at $1.10 each, please let me know!
(1) I'm told the nit-wit CEO is being paid 4 million to step down, while thousands of shop floor workers are facing unemployment at Christmas!
(2) It's amazing what a 90% OFF sale does to the human mind. I bought $2,500 worth of crap that I don't need for just $250.
Did I save $2,250 or just lose $250?
If anyone needs 500 galvanized bolts (without washers or nuts), or 50 garden sprinklers at $1.10 each, please let me know!
betterlatethannever
New Member
Fraser said:
I love the insight that you "afforded" yourself,and I think that you know the answer the "that" question :lol:
Merry Christmas
Should have bought the fake garlic: Masters fire sale: the weirdest, saddest stuff left :lol:
shinymetal
Well-Known Member
The term "piss off" comes from when a man uses his fire hose to piss the skid marks off the inside of a toilet bowl.
I did make that up, but I reckon there is a pretty good chance it's true.
I did make that up, but I reckon there is a pretty good chance it's true.