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Ah, but we're squishy. Ants have armor plating.Some ants do indeed have wings, and they do fly, like other flying insects. Several years ago, the building I lived in had an ant problem, and in the spring, these ants went into a flying form. At first, we thought we were seeing flies, but we finally realized that they were flying ants. This lasted for about a month or two, until they finally reverted back into a nonflying form (or died off or whatever).Dick
Yeah, that makes sense, so the ant would still not die when it is dropped from the airplane? Or will the pressure applied to the ant have killed it before reaching the airplane? But I understand that the terminal velocity of an ant is relatively small compared to us, as they have a smaller surface area etc. But surely if must do SOME harm to an ant? Because, if we fall with the speed of terminal velocity, we would most definitely die. Even if the speed of terminal velocity of an ant is small, wouldn't it affect its small body?
Quote from: seanahnuk on 11/04/2007 14:30:44Yeah, that makes sense, so the ant would still not die when it is dropped from the airplane? Or will the pressure applied to the ant have killed it before reaching the airplane? But I understand that the terminal velocity of an ant is relatively small compared to us, as they have a smaller surface area etc. But surely if must do SOME harm to an ant? Because, if we fall with the speed of terminal velocity, we would most definitely die. Even if the speed of terminal velocity of an ant is small, wouldn't it affect its small body?It you take it up high enough, it may have problems with the cold.The ants body is small, but it is relatively strong for its small size (again a function of compactness - you drop an elepjant from an even lower height, it would probably die even where a human would survive).
It's to do with the effect of viscosity. When you drop yourself or the ant out of the plane you start to accelerate downwards because of the force of gravity acting on you. As you pick up speed the air rushing past causes a dragforce which tends to slow you down. When these two effects cancel out the force of gravity is the same as the drag force, at this point you stop accelerating. For a human it's about 120MPH. For an ant it will be a lot smaller.If you model the person and the ant as spheres with equal density and radii in the ratio 1000 to 1 falling through air at normal temperature and pressure, then you are probably a physicist and know about the Stokes Einstein equation.
I was just curious about this. Because if you drop an ant from shoulder height, or a 2-story high place, I'm pretty sure that the ant still lives. But it would seriously injure us humans, because of our mass, etc. But what if you drop an ant from an airplane or somewhere really high?Just a curiosity..
Yes. For a human, lets say the terminal velocity is 120MPH. In which case, we would most definitely die.For an ant. Ok, it wound be relatively SMALLER than a human. But wouldn't it still be the same ratio? Therefore, still having a massive impact on such a little guy?
Quote from: seanahnuk on 11/04/2007 20:32:32Yes. For a human, lets say the terminal velocity is 120MPH. In which case, we would most definitely die.For an ant. Ok, it wound be relatively SMALLER than a human. But wouldn't it still be the same ratio? Therefore, still having a massive impact on such a little guy?Don't know that it would be pro-rata (things like Reynolds numbers come into it - that is the answer to the puzzle why bumble bees can fly despite the fact that a scaled up bumble bee would never fly).If one assumes for simplicity that it is pro-rata, then an ant is about 5mm long, while a human being is about 2 metres tall, that is a ratio of 500:1. If the terminal velocity of a human is 120mph, then a 500:1 ratio would mean 0.24mph - I think it would seem preposterous to assume an ant would be harmed by an impact of 1/4 of 1mph.The above assumes that the terminal velocity is pro-rata, and I doubt that the calculation is anywhere near as simple as that, so I don't think that is the actual right answer, but it does show that it is quite easy for the terminal velocity to be perfectly within tolerable levels for an ant.
Yes, but 1/4 mph might still be a huge impact on a fly? Just like 120mph for us is? We cannot just assume that since 1/4mph is slow for us and not damaging, that it will be the same for flies?
Quote from: seanahnuk on 12/04/2007 00:31:07Yes, but 1/4 mph might still be a huge impact on a fly? Just like 120mph for us is? We cannot just assume that since 1/4mph is slow for us and not damaging, that it will be the same for flies?The reason why I think that 1/4 cannot cause harm to an ant is because so many natural events in the environment occur at much higher speeds than that.Aside from ants, any flying insect will regularly suffer impacts greater than this (just gently swat a fly or a bee, and you are exceeding that speed - a heavy swat may harm them, but a gentle one will not - even their own flying speed will exceed that speed).I would expect that that even falling from table height would allow an ant to reach terminal velocity, yet this kind of fall would not be that uncommon for an ant.
You've seen rocks floating in the air. Very small rocks, with a lot of surface area in proportion to their mass. They are called dust.I think an insect of any kind would fall slowly enough to land safely.
You've seen rocks floating in the air. Very small rocks, with a lot of surface area in proportion to their mass. They are called dust.
Quote from: BillJx on 12/04/2007 03:44:26You've seen rocks floating in the air. Very small rocks, with a lot of surface area in proportion to their mass. They are called dust.Dust only appears to be floating from our perspective - the dust is in fact falling through the air (albeit, as you say, very slowly), but small pockets of air air rising, and the dust is sometimes falling slower than the pocket of air it is in rises, so the nett effect from our point of view is to see the dust itself rise.Even humans can do this - in a tornado - it is just that to a small spec of dust, even the ordinary turbulence of warm air will feel like lots of tornadoes blowing about.
Soo... Assuming that the terminal velocity for a human is 120mph, and for an ant is 0.25mph. 0.25mph is roughly the speed of.. Ok, nothing that slow.. Yes, I can see how it won't affect the ant at all, seeing that our hands swatting a fly would probably be like atleast 1mph and it sometimes doesnt even die.But, 0.25mph for an ant. How fast would that feel for an ant? Because, thinking as a human, 120mph is FAST. Even the wind at 120mph means shed roofs, fences falling down. So would 0.25mph still be QUITE fast for an ant? But won't affect them hardly as much as 120mph?
It takes a dexterous hand to coax a whip to crack. Now researchers report that they have discovered the mechanism responsible for the startling sound. It has long been thought that the crack results from the tip of the whip traveling fast enough to break the sound barrier and create a sonic boom. But the new findings suggest otherwise. Apparently, it's the loop in a whip that is the real noisemaker.Though by no means a master whip cracker, Alain Goriely of the University of Arizona was nonetheless intrigued by the phenomenon and set out to study it at a theoretical level. Together with Tyler McMillen, a graduate student in applied mathematics, he modeled the behavior of the leather strips in a paper to be published in Physical Review Letters. Previous whip work (one of just three papers on the subject in the past century) had resulted in the puzzling observation that the sonic boom occurs when the tip of the whip is traveling at about twice the speed of sound. But if the tip were truly the cause of the crack, why wasn't the sound heard earlier, when the tip first reached the speed of sound? Goriely and McMillen's calculations have revealed the answer. "The crack of a whip comes from a loop traveling along the whip, gaining speed until it reaches the speed of sound and creates a sonic boom," Goriely says. He notes that even though some parts of the whip travel at greater speeds, "it is the loop itself that generates the sonic boom."Although the whip's tip has lost the distinction of being the source of the menacing crack, it is still a force to be reckoned with: according to Goriely's calculations, "the tip can reach speeds more than 30 times the initial speed [of the whip]."
Thanks for that. So the whip travels at like 30,000mps?
And also, don't you think an ant dropped from a building, would have a speed of more than 0.25mph? I was thinking more like atleast 10, even though it is a small fella.
So our ant should fall at half a centimetre per second. OK it looks like that's a bit low to me, but I did say I was making some assumptions.