help me with a term paper?

Why don't we all calm down here.

If you don't like what someone is posting, instead of starting a flame war, ignore the thread, PM/email a moderator or report the thread. It is really that simple.

On that note, if I (or any of the other mods) find that an excessive amount of threads are being made about somewhat outrageous things, we will deal with it. AC mods pay multiple visits a day to all parts of this forum. Dealing with it can range from simply closing a thread, to banning the poster... of course, all depending on how severe something is.

For now, these posts aren't hurting anyone, so we'll let things go as they are.

Just a fair warning though, "trolling" is frowned upon in internet forums, if I or any other mod feel that this is the case, we will close threads without warning. At the same time, starting up arguements/fights etc. is also frowned upon, no matter what the intention. The ends cannot justify the means.

Lets keep this thread on topic.

-Richer
 
<wanders ever-so-slightly off-topic for a moment>

Personally, I think "what-if" questions are kinda cool, no matter whether they are posted in a joking light or not.

If someone posts an unusual question like this, it makes me start to think, even if it's just about "how" the experiment would be carried out, if not what the result of the experiment would be.

I seem to remember a thread about measuring a fish's intelligence (which also degraded into a flame war, but that's water under the bridge...), and it gave me a lot of new ideas, and made me think of biology in a slightly different light.

All of this is to say, Hans, even if you don't perform this experiment, maybe someone else will, and that's all that matters in my mind. :) It's all about learning, and experimentation is the most human type of learning there is.

Cheers all!
 
i am being falseley accused! just because i dont post "what should i put in my 20 gallon tank" or "what kind of fish did i just buy" doesnt mean im trolling! im still working on the experiment by the way, im going to be using black molly, platy, sword tale, and guppy fry
 
I agree!
Guys calm down!
At the end of the day it is an interesting thought and its clear to see that some people have had some enjoyment from this post!
Even if Hans is not actually doing a paper on it he should feel like he can ask questions like this!
Oh and if we say that the fry can probably cover 1/3 metre in about a tenth of a second. That roughly equates to:
3 1/3 metres per second
or
12 Kilometres per hour
 
I think the point also already came up that it would be easier if there was no water current... because then we would just be calculating thier speed in still water, as opposed to against a current (or force) which would definately slow them down.

although i guess water itself is considered a force just as gravity is?

thats it! we need to send these little tykes into space! air-tight vacum chambers with no gravity! then we'll really see 'em fly.
 
im not a physics major or anything but wouldnt a current be created when the fish swims threw the water, almost the same as if the water moved passed the fish and it was able to maintain its position?
 
Re: <wanders ever-so-slightly off-topic for a moment>

Originally posted by pinballqueen
Personally, I think "what-if" questions are kinda cool, no matter whether they are posted in a joking light or not.
Click to expand...

It's also the basis of science, where would we be today if a bunch of people throughout history hadn't asked "what if ...?" ?

Hans, I don't think that you were being accused of trolling.

Zin, it's been a while, but as I recall, depending on the size and speed (and certainly shape) of an object, hydrodynamics may be a little different. I gotta run now, but if you do a search for Reynold's number (I think that's the one) it may clear stuff up.

cheers
 
no bevause its not that fry can swim for a great length of time that is amazing, the amazing part is the BLASTS of speed they get when something nips at them.

btw do you know that a dragonfly nymph hold water in its butt, and when it needs to, it contracts and shoots the lil guy along liek a rocket!@ now tahts is funny! HAHA
 
I read up on some of the reynolds number, from what i got its for calculating turbulance, which i did a little more searching and can be caused by either the media flowing passed a object or the object moving threw the media. Now what i was thinking was that a fish swimming against a current is like a object in a wind tunnel. Like when fish swim against a current from a filter output, the water is moving at -x and the fish is moving at x(probably using variables wrong but i think the idea is there) then the fish moves 0. Wings and other 'shapes' get lift in a wind tunnel, i dont see why a fish wouldnt get <some word> in water.

Its also possible im incredibly ignorant and have no clue what im talking about(most likely)


heres a link i found pretty interesting
http://www.lsc.usgs.gov/SPN.asp?StudyPlanNum=09030-01
 
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You're probably not too far off base zin, I'm no physicist either. Good to hear though, I remembered the right number!:P It does have to do with turbulence, specifically with how a fluid moves around an object. At high Reynolds numbers flow is turbulent, you get those drag spirals, at low you get laminar flow, the fluid just moves around the object smoothly.

The point I was trying to make (ineffectually) was that I'm not sure that the water speed would indicate how fast they can go, for example, if the water just slides around them smoothly. In that case they don't have to work as hard to swim upcurrent as if they had a lot of drag forces to work against.

Of course, seeing as my fluid dynamics skills are immeasurably close to zero, I can't really say.

Good link, although that may be the longest abstract I've ever read! It seems to dissuade our intrepid young researcher (that would be Hans) from using a moving water method.
 
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