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# Things you thought you knew about, but really did not

## Posts

• Registered User regular
OptimusZed wrote: »
I don't know what you mean by that last sentence, though.
Basically that atmospheric pressure, the same thing that is responsible for the pressure differential and thereby the lift, is constantly exerting a downward force on every surface within our atmosphere. The exception I guess would be something that was sufficiently distant from our surface as to fall into a range where the downward force from the air above was counteracted by the lift from the previously discussed pressure differences.

Downward air pressure at sea level is around 14.7 psi. I imagine that would more than counter the lift from the ambient pressure differential.
Er, that part's not right. Air pressure doesn't exert a net downward force—quite the opposite, in fact; you get a small lift due to buoyancy (man that's a fun word to type). The same 100 kPa pushing down on you is pushing up on you as well (and in fact a little more than that is pushing up on you).

This does not address the fundamental question: why can a plane fly upside down?

The angle of attack explanation is much more satisfying in this regard.
What? I'm not saying that this effect explains an airplane's lift. Are you responding to the wrong post?

If not, I don't understand your question.

The planes designed to fly upside down have symmetric airfoils which have a coefficient of lift at almost exactly zero at zero angle of attack. So, everything is pretty much mirrored on the angle of attack. Look, there are thousands of airfoil designs out there and each have their specific purpose.

parabol
• Registered User regular
Demerdar wrote: »
OptimusZed wrote: »
Honk wrote: »
Demerdar wrote: »
Okay guys.

Airfoils:

Spoiler:

I hope that made sense. I am a graduate fluid mechanics student, so I oughta know.
This is absolutely the classic wrong explanation and you should be very ashamed.

Also, a symmetric airfoil at zero angle of attack does generate a small amount of lift. I'll let you guys figure out why. A hint, if you need one:
Spoiler:

The answer did not become apparent! YOU LIED!
Off the top of my head I'd say that it's because the air below the foil has just a hair more pressure than the air over the top of it. This is due to the compression due to gravity acting on the column of air, and would generate a minuscule amount of lift. It would probably also be canceled out or exceeded by the ambient downward air pressure that everything in our atmosphere experiences.
Correct! The air in the atmosphere is not uniformly dense. On airplane-like velocity scales and physical dimensions this effect is near zero, but when you're moving at ten kilometers per second and are many meters tall, the upward force generated can lift the body right back up out of the atmosphere (if it was coming in almost-tangentially to begin with).

I don't know what you mean by that last sentence, though.

Are you debating between zero lift and "close to zero lift" here? And I am talking about airfoils, which operate at much lower Reynolds numbers than what you are talking about. In fact, what's wrong with my explanation?
Maybe I wasn't clear, but I'm talking about two unrelated effects--the tiny bit of lift generated due to the density gradient in the earth's atmosphere (which matters not at all for airplanes) and the general "airfoil generating lift at subsonic speeds" which is a bigger misconception that a lot of people have. The density gradient thing matters only when you're going ridiculously fast. The whole "faster over the top, yadda yadda Bernoulli, ta-da pressure differential" misconception is alarmingly prevalent.

A much lower-level (but physically correct) explanation is that the wing is like a very efficient rocket--it is pushing air downward and getting a net upward force. The air leaves the wing with a downward momentum component that it didn't have before. The usual equations for force and momentum apply. Wings are efficient compared to something like a rocket (or a vertically-oriented jet engine) because they actuate a much, much greater mass of air. Insert your basic momentum-energy relations here and you have a very low-level (but totally correct) view of how a wing works.

If you zoom into the flow field around the wing, you can start to ask why it has that downward momentum component--that is, in what manner does the wing act to push this air downard? You can imagine the air as being a bunch of discrete points bouncing off a wing, but while that's the right principle it's not a good description of how air actually behaves (the particles interact with each other way, way too much for that to be correct).

If you actually look at an experimentally-measured flow field, it becomes clear that the airfoil is actually pulling the air downward behind it moreso than pushing it down. You can visualize this (kind of) as if the top of the wing were half of a rocket nozzle; the air has some pressure (hence some potential energy) and as the wing passes it the air is free to expand downward and backward. It converts some of its potential energy to kinetic, and its static pressure drops. This is where you could normally use your Bernoulli explanation for the lower static pressure and higher velocity--but you'd have the causality all reversed. The air doesn't have lower pressure because it's moving faster; it is moving faster because it has expanded backward from the leading edge of the wing. It's sort of expanding downward and backward into the vacuum* left after the wing moved past. Also, the Bernoulli equation doesn't technically hold as the flow is viscous and the wing imparts energy to the flow (or removes it depending on your frame of reference), but the working principle is mostly there.

The thing that is wrong about your original explanation is your assertion that the air is faster over the top because the path is longer (two particles split at the front don't have to meet at the back). That's not just a simplification, it's genuinely incorrect. It is taught very widely, though, and a lot of otherwise well-informed people still believe it to be correct. It famously fails to make clear how inverted flight is possible.

I would also argue that it's a lot less informative to use the Bernoulli equation in this case to say that the pressure is lower because the velocity is higher rather than the other way around. The equation itself says nothing about the causality (causality is kind of an invented thing, really; the equations never care) but it seems to me much more informative to go about things from this perspective.

*There's no actual vacuum; just a low-pressure region. It would be a vacuum if the air didn't expand back down into that region though (and if we also ignore viscosity, which itself contributes to making the streamlines follow the contours of the wing).

I understand the issue, and I am aware that the Bernoulli principle only applies under idealized conditions, after all it can be derived from both conservation of momentum and conservation of energy.

That was a pretty stimulating read, you have good physical intuition. What's your background?

parabol
• Registered User regular
OptimusZed wrote: »
Take it back, Ahava.

Take it back before the internet attacks.

hey, you sit through half a year of watching the same Bill Nye episode (Solid, Liquid, Gas *snort snort Seinfeld snort*) And you tell me that you won't have just a littttle bit of hatred for the man.

I hate the substitute even more, but still.

Also,

I thought I knew just how stupid the American Public could get....

Apparently, I was wrong

Oh god. So many racist white people in the comments.

• Who needs a medical license when you've got style? Registered User regular
I had no idea mine was so huge until my sister saw it and freaked out. I've since pinpointed my huge uvula as the source for some major throat problems and am having it trimmed in a couple of days.
Cartoons ruined my life. True story.

I had a UPPP done and my uvula was removed. I don't have a uvula! I am uvulaless.

I am comforted by Richard Dawkins’ theory of memes. Those are mental units: thoughts, ideas, gestures, notions, songs, beliefs, rhymes, ideals, teachings, sayings, phrases, clichés that move from mind to mind as genes move from body to body. After a lifetime of writing, teaching, broadcasting and telling too many jokes, I will leave behind more memes than many. They will all also eventually die, but so it goes. - Roger Ebert, I Do Not Fear Death
• (citation needed)Registered User regular
Incenjucar wrote: »
Oh god. So many racist white people in the comments.

I think there's enough racism to go around for everyone in that debacle.

The sheer cash value of the mountain of demands that kid's mother makes would buy 40 acres and a mule for every person in the Midwest.

- \$1.25 million in damages
- System-wide campaign to end teacher-on-student violence
- \$13,500 in Wal-Mart store credit
- Full tuition to college of choice
- Tennis lessons
- Season tickets to the opera
- Free emotional counseling for a decade
- Three-week African luxury vacation
- Musical instruments
- Two trips to Disney world
- A meeting with President Obama
- Complete re-model of their existing home
- Paid mortgage of said home
- Complete family medical coverage for a decade
- Consulting position with ISD for \$15,000/month.

• Registered User regular
Oh I've got a neat one. Human bodies seem to give up after a while, but it turns out that there are probably choke points that decide how long you live. It's pretty logical really that certain organs will give up first (looking at you heart).

The liver is a fighter though, it is estimated that a human liver could become 150-160 years old in use - no problem. Partial transplantations of the liver are no problem either, you cut out half of it, wait 5 weeks and both split pieces have grown in to the size of full livers.

• Registered User
Honk wrote: »
Oh I've got a neat one. Human bodies seem to give up after a while, but it turns out that there are probably choke points that decide how long you live. It's pretty logical really that certain organs will give up first (looking at you heart).

The liver is a fighter though, it is estimated that a human liver could become 150-160 years old in use - no problem. Partial transplantations of the liver are no problem either, you cut out half of it, wait 5 weeks and both split pieces have grown in to the size of full livers.

Livers are the energizer bunny of the body. They do a lot of tasks too.
Wiet wrote: »
Oh! Talking about Jesus: finding out that God is kind of an asshole was quite the surprise. Like: I always enjoyed the story of Job, but re-reading it later made me realise that the only reason God made Job suffer that much was because of a bet with Satan. And lets not delve into the Old Testament, my religion teachers were wise enough to skip most of those stories. Like the one where a young guy makes fun of an old guy walking through town and God sends down wild bears to murder all the boys in the village.

Actually the negative view of Satan is a Christian/Islamic thing. Satan does thing we consider bad in the Old Testament, but his role in Judaism is "The adversary", or to be more specific "the opponent." He's like that guy that always questions and challenges, not hates humanity and wants them to suffer in hell.
I never really understood just how BIG big cities were until I moved from a tiny, 3,000 people town, to the Dallas/Fort Worth metroplex. My mind was completely, utterly blown from the vastness of concrete and roads in that area.

The needs of a city are impressive too- even if everyone in New York ate only a pound of food a day, that's still be millions and millions of pounds of food.

• (citation needed)Registered User regular
Honk wrote: »
Oh I've got a neat one. Human bodies seem to give up after a while, but it turns out that there are probably choke points that decide how long you live. It's pretty logical really that certain organs will give up first (looking at you heart).

The liver is a fighter though, it is estimated that a human liver could become 150-160 years old in use - no problem. Partial transplantations of the liver are no problem either, you cut out half of it, wait 5 weeks and both split pieces have grown in to the size of full livers.

Actually, the biggest hurdle to longevity is the brain and nervous system. Just about every other part of your body is repairable or replaceable. Not only is the nervous system incapable of being significantly worked upon or transplanted, most studies show that the odds of sustaining a debilitating neurological injury (stroke) or disease (cancer, Parkinson's, tumors) increases to almost 100% along the age curve.

Just about all of your abdominal or thoracic organs (except genitals) can be redacted or replaced and work just as well, and so can your eyes for the most part.

However, people with genetic aberration are basically fucked. Sickle cell disease, cystic fibrosis, DIC patients? Your problems can't be solved with any amount of transplantation. Scientific advancement is your only hope.

• Registered User regular
Incenjucar wrote: »
Oh god. So many racist white people in the comments.

I think there's enough racism to go around for everyone in that debacle.

The sheer cash value of the mountain of demands that kid's mother makes would buy 40 acres and a mule for every person in the Midwest.

She's merely batshit insane and opportunistic with racism as her primary excuse.

• Registered User regular
Honk wrote: »
Oh I've got a neat one. Human bodies seem to give up after a while, but it turns out that there are probably choke points that decide how long you live. It's pretty logical really that certain organs will give up first (looking at you heart).

The liver is a fighter though, it is estimated that a human liver could become 150-160 years old in use - no problem. Partial transplantations of the liver are no problem either, you cut out half of it, wait 5 weeks and both split pieces have grown in to the size of full livers.

This always made me wonder why you couldn't remove part of the liver from someone at high risk for liver damage (say someone who just contracted hep C, or a chronic alcoholic who had not yet developed significant liver damage), freeze or preserve it somehow, then use it for a transplant 10 or 15 years down the line. I'm sure preservation is the limiting factor, but there have been huge advances in tissue preservation lately.

Here's a question similar to the airplane flying upside thing: I'm nearsighted, and I understand that glasses work by changing the focal point of light going through them. Why is it, though, that I can literally turn my glasses around and look through them backwards and still see perfectly fine?

Edit: Also I think the reason for helium in scuba tanks isn't due to anything with breathing but instead because nitrogen and oxygen at high pressures both become supersaturated in blood plasma and bubble out on return to low pressures, while helium doesn't and thus makes a good filler to keep you from breathing in too much oxygen too quickly and therefore getting oxygen dissolved directly in the blood plasma as opposed to just in the hemoglobin.

• Registered User regular
Here's a question similar to the airplane flying upside thing: I'm nearsighted, and I understand that glasses work by changing the focal point of light going through them. Why is it, though, that I can literally turn my glasses around and look through them backwards and still see perfectly fine?

Probably because your lenses are most likely symmetrical?

• Registered User regular
Honk wrote: »
Oh I've got a neat one. Human bodies seem to give up after a while, but it turns out that there are probably choke points that decide how long you live. It's pretty logical really that certain organs will give up first (looking at you heart).

The liver is a fighter though, it is estimated that a human liver could become 150-160 years old in use - no problem. Partial transplantations of the liver are no problem either, you cut out half of it, wait 5 weeks and both split pieces have grown in to the size of full livers.

This always made me wonder why you couldn't remove part of the liver from someone at high risk for liver damage (say someone who just contracted hep C, or a chronic alcoholic who had not yet developed significant liver damage), freeze or preserve it somehow, then use it for a transplant 10 or 15 years down the line. I'm sure preservation is the limiting factor, but there have been huge advances in tissue preservation lately.

That is an interesting question. Yes preservation is most definitely the limiting factor, cutting a liver in two and transplanting one of the parts to someone else is common practice. Not very common but it's done all over the world.

So you could most definitely cut your own in half and save one for later - if we had better ways to preserve it. At this point we can't just freeze organs, cold slows organs down and makes them last longer on their way to a transplantation but we're talking about hours here. Actually freezing organs would cause the cells to rupture and take irreparable damage (freezer burn) because all our cells contain large quantities of water.

Also more to the point is that hospitals generally won't transplant an already infected organ to a person - in your example the patient's better liver-half would already carry the hep C infection. The hypothetical transplant would make him better but he'd still be replacing a damaged liver with a slightly less damaged one. Guidelines differ though, I know that some patients with liver failure here in Sweden can be transplanted with liver grants that carry certain lesser diseases.

• Registered User regular
Kay wrote: »
Here's a question similar to the airplane flying upside thing: I'm nearsighted, and I understand that glasses work by changing the focal point of light going through them. Why is it, though, that I can literally turn my glasses around and look through them backwards and still see perfectly fine?

Probably because your lenses are most likely symmetrical?

Well the lenses are visibly curved, but apparently after reading the curvature isn't important to the lensing effect but is just to reduce distortion.

In regards to the hep c thing, the patient is already infected with hep c so that doesn't really matter, and the consequences of further liver damage is likely small compared to the organ rejection and constant immunosuppressants needed for a graft from another person.

• Registered User regular
Kay wrote: »
Here's a question similar to the airplane flying upside thing: I'm nearsighted, and I understand that glasses work by changing the focal point of light going through them. Why is it, though, that I can literally turn my glasses around and look through them backwards and still see perfectly fine?

Probably because your lenses are most likely symmetrical?

Well the lenses are visibly curved, but apparently after reading the curvature isn't important to the lensing effect but is just to reduce distortion.

In regards to the hep c thing, the patient is already infected with hep c so that doesn't really matter, and the consequences of further liver damage is likely small compared to the organ rejection and constant immunosuppressants needed for a graft from another person.

A better preventative measure would be to take a biospy of liver cells early in life and culture it. The liver - due to it's regenerative powers and relative structural simplicity - is a prime organ to be grown in vitro for transplantation, using those tissue-matrix techiques.

Ground-floor health insurance of the next century is totally going to be based on living tissue culture like The Island - just with less murdering sentient lifeforms.

Dis' wrote: »
Cancer is when cells stop letting the body mooch off their hard work - clearly a community of like-minded cells should isolate themselves and do the best job each can do, even if the rest of the body collapses!
• Registered User regular
This reminds me of the fact that when I was a kid I always thought that if the earth stopped spinning (or turned backwards by superman) everything would fly off because for some reason I figured that gravity was caused by centrifugal force, but its not it's actually caused by mass.

Along this vein: due to the fact the Earth is rotating, the apparent direction of "down" is not toward the center of the Earth unless you're standing on the equator or one of the poles. This also gives rise to Coriolis forces on anything moving relative to the Earth (within the atmosphere, at least). One of the best examples of this is seen when an object is moving for a long time: the Foucault Pendulum is exactly such an object, and was used to demonstrate that the Earth was, in fact, rotating. (This principle extends to anything moving in the atmosphere as well, which is what determines the direction weather systems like Hurricanes rotate.)

• Registered User regular
Emissary42 wrote: »
This reminds me of the fact that when I was a kid I always thought that if the earth stopped spinning (or turned backwards by superman) everything would fly off because for some reason I figured that gravity was caused by centrifugal force, but its not it's actually caused by mass.

Along this vein: due to the fact the Earth is rotating, the apparent direction of "down" is not toward the center of the Earth unless you're standing on the equator or one of the poles. This also gives rise to Coriolis forces on anything moving relative to the Earth (within the atmosphere, at least). One of the best examples of this is seen when an object is moving for a long time: the Foucault Pendulum is exactly such an object, and was used to demonstrate that the Earth was, in fact, rotating. (This principle extends to anything moving in the atmosphere as well, which is what determines the direction weather systems like Hurricanes rotate.)

I always thought it was funny that while hurricanes and typhoons pretty much always rotate in the proper coriolis direction from where they formed, tornados will occasionally spin the wrong way just out of spite.

• Registered User regular
Emissary42 wrote: »
This reminds me of the fact that when I was a kid I always thought that if the earth stopped spinning (or turned backwards by superman) everything would fly off because for some reason I figured that gravity was caused by centrifugal force, but its not it's actually caused by mass.

Along this vein: due to the fact the Earth is rotating, the apparent direction of "down" is not toward the center of the Earth unless you're standing on the equator or one of the poles. This also gives rise to Coriolis forces on anything moving relative to the Earth (within the atmosphere, at least). One of the best examples of this is seen when an object is moving for a long time: the Foucault Pendulum is exactly such an object, and was used to demonstrate that the Earth was, in fact, rotating. (This principle extends to anything moving in the atmosphere as well, which is what determines the direction weather systems like Hurricanes rotate.)

I always thought it was funny that while hurricanes and typhoons pretty much always rotate in the proper coriolis direction from where they formed, tornados will occasionally spin the wrong way just out of spite.
Tornadoes are daemonic engines of destruction, unbeholden to such quaint natural phenomena as Coriolis Force.

We're reading Rifts. You should too. You know you want to. On Hiatus!

GT: batshido Hit me up on ME3.
• __BANNED USERS regular

• Registered User regular
Honestly, as a native Kansan I never really found tornadoes to be terribly scary. They're just kind of a fact of life, like the train sitting at the crossing or the yearly drought/flood.

Just the idea of an earthquake, though, is terrifying. I've never been in one, but I'd probably shit myself.

We're reading Rifts. You should too. You know you want to. On Hiatus!

GT: batshido Hit me up on ME3.
• Registered User regular
OptimusZed wrote: »
Honestly, as a native Kansan I never really found tornadoes to be terribly scary. They're just kind of a fact of life, like the train sitting at the crossing or the yearly drought/flood.

Just the idea of an earthquake, though, is terrifying. I've never been in one, but I'd probably shit myself.

I'm kind of the same way with hurricanes, nothing less than a high cat 4 or cat 5 really worries me these days

• __BANNED USERS regular
OptimusZed wrote: »
Honestly, as a native Kansan I never really found tornadoes to be terribly scary. They're just kind of a fact of life, like the train sitting at the crossing or the yearly drought/flood.

Just the idea of an earthquake, though, is terrifying. I've never been in one, but I'd probably shit myself.

What about a blizzard that leaves 3 feet of snow on the ground?

• Registered User regular
OptimusZed wrote: »
Honestly, as a native Kansan I never really found tornadoes to be terribly scary. They're just kind of a fact of life, like the train sitting at the crossing or the yearly drought/flood.

Just the idea of an earthquake, though, is terrifying. I've never been in one, but I'd probably shit myself.

What about a blizzard that leaves 3 feet of snow on the ground?
That's becoming a yearly thing too. Along with the 3 weeks in February that my folks don't have electricity.

We're reading Rifts. You should too. You know you want to. On Hiatus!

GT: batshido Hit me up on ME3.
• veni, veneri, vamoosi Registered User regular
Were you around for the ice storm we had about 5 years ago? That was nasty.
I learned that if you live in the dorm that gets power back 2 days before the others, you find out you have a lot of friends you didn't know about who want a hot shower.

• Registered User regular
I actually moved to Philly in January of '05. So I missed out on all that fun.

My mom and dad got to spend over a month without heat afterwards, though. It's a good thing they had the dogs to keep them warm.

Now they've got a generator wired straight into the grid for the house in case it happens again.

We're reading Rifts. You should too. You know you want to. On Hiatus!

GT: batshido Hit me up on ME3.
• Registered User
OptimusZed wrote: »
Honestly, as a native Kansan I never really found tornadoes to be terribly scary. They're just kind of a fact of life, like the train sitting at the crossing or the yearly drought/flood.

Just the idea of an earthquake, though, is terrifying. I've never been in one, but I'd probably shit myself.

I'm the same way (re: just a fact of life) with wildfires and, to a lesser extent, earthquakes.

But, you know, lolCalifornia

• Registered User regular
Coriolis force doesn't make your toilet drain in a particular direction. Most people think it does, but Coriolis force only effects systems that are several orders of magnitude bigger than a toilet bowl.

• Registered User
Honk wrote: »
Honk wrote: »
Oh I've got a neat one. Human bodies seem to give up after a while, but it turns out that there are probably choke points that decide how long you live. It's pretty logical really that certain organs will give up first (looking at you heart).

The liver is a fighter though, it is estimated that a human liver could become 150-160 years old in use - no problem. Partial transplantations of the liver are no problem either, you cut out half of it, wait 5 weeks and both split pieces have grown in to the size of full livers.

This always made me wonder why you couldn't remove part of the liver from someone at high risk for liver damage (say someone who just contracted hep C, or a chronic alcoholic who had not yet developed significant liver damage), freeze or preserve it somehow, then use it for a transplant 10 or 15 years down the line. I'm sure preservation is the limiting factor, but there have been huge advances in tissue preservation lately.

That is an interesting question. Yes preservation is most definitely the limiting factor, cutting a liver in two and transplanting one of the parts to someone else is common practice. Not very common but it's done all over the world.

So you could most definitely cut your own in half and save one for later - if we had better ways to preserve it. At this point we can't just freeze organs, cold slows organs down and makes them last longer on their way to a transplantation but we're talking about hours here. Actually freezing organs would cause the cells to rupture and take irreparable damage (freezer burn) because all our cells contain large quantities of water.

Also more to the point is that hospitals generally won't transplant an already infected organ to a person - in your example the patient's better liver-half would already carry the hep C infection. The hypothetical transplant would make him better but he'd still be replacing a damaged liver with a slightly less damaged one. Guidelines differ though, I know that some patients with liver failure here in Sweden can be transplanted with liver grants that carry certain lesser diseases.

Maybe this doesn't apply exactly, but I recently learned that some doctors are questioning treatment for Hep C because it works on paper, they can get the viral load to near nil, but patients aren't living any longer.

• Registered User
Well, while you're on words that sound differently from the way they're spelled:

For years, I pronounced "melancholy" as "me-ann-cho-lee". Learned it was "melon-collie" at an advanced age.

And apparently "victuals" is pronounced "vittles". I assumed it should rhyme with "rituals".

But those are just words, and someone else's idea of how to pronounce them. Shakespeare had like 8 different ways of spelling his own name. In the long run, consensus wins.

• Registered User regular
Except for really big ones, earthquakes aren't that big a deal. Most of the time you barely figure out what's happening before it's over.

• Registered User
I believed the whole "it's theoretically impossible for bumblebees to fly" thing until one of my professors proved otherwise. It uses a process called dynamic stall that temporarily increases lift dramatically. It's been tried in helicopters, but the blades can't alter their pitch fast enough.

• Registered User regular
RUNN1NGMAN wrote: »
Coriolis force doesn't make your toilet drain in a particular direction. Most people think it does, but Coriolis force only effects systems that are several orders of magnitude bigger than a toilet bowl.
It is amazing how many people insist on this.

• Registered User regular
RUNN1NGMAN wrote: »
Coriolis force doesn't make your toilet drain in a particular direction. Most people think it does, but Coriolis force only effects systems that are several orders of magnitude bigger than a toilet bowl.
It is amazing how many people insist on this.

I used to think this until I took a meteorology class, but I blame Mr. Wizard.

He did a demonstration where he had a tub of water with a drain plug and put it on a playground merry-go-round. He spun it in one direction, and the water drained clockwise. Other direction—counter-clockwise. I missed the part where the merry-go-round represented Earth.

• Registered User regular
Basilicus wrote: »
And apparently "victuals" is pronounced "vittles". I assumed it should rhyme with "rituals".

Wait for real?

Makes no sense, but whatever.

• Registered User
Julius wrote: »
Basilicus wrote: »
And apparently "victuals" is pronounced "vittles". I assumed it should rhyme with "rituals".

Wait for real?

Makes no sense, but whatever.

And here I had the exact opposite problems. I've only ever heard it pronounced, so I've always assumed it was spelled (and I've written it this way a couple of times) "vittles".

• Registered User regular
Demerdar wrote:
I understand the issue, and I am aware that the Bernoulli principle only applies under idealized conditions, after all it can be derived from both conservation of momentum and conservation of energy.

That was a pretty stimulating read, you have good physical intuition. What's your background?
I'm an aerospace engineer, though I haven't done any real work on hardware so far.
Julius wrote: »
Basilicus wrote: »
And apparently "victuals" is pronounced "vittles". I assumed it should rhyme with "rituals".

Wait for real?

Makes no sense, but whatever.
Huh, I didn't know this. That's not a word I would normally ever use in speech, but I've always subvocalized it as sort of like "rituals" as well.

Here's one most of you guys are probably getting wrong even as you read it: "dissect". It's pronounced like "dis sect", not "die sect", although the latter (wrong) pronunciation is gaining a lot of momentum simply as a result of how many people screw it up. It really is the prefix "dis" and the root word "sect"; the prefix "di" and the root word "sect" would together mean the same thing as "bisect", which would be pointless as that's already a common word. Also, it'd be spelled "disect" in that case.

MWO User Name: Gorn Arming
• Registered User regular
I'm all for banning pronouciation things (in this thread), largely since most of you are American and thus doomed from the start (seriously, 'Erbs without the rest of t'accent) but again, apparently the pronouciation of the letter 'H' is something that no one really knows. Ewts and Nothers etc

Seriously, Z is reserved for special occasions. I don't believe people actually use it as much as microzoft demands. Ostrasising for instance.

• Registered User regular
Here's one most of you guys are probably getting wrong even as you read it: "dissect". It's pronounced like "dis sect", not "die sect", although the latter (wrong) pronunciation is gaining a lot of momentum simply as a result of how many people screw it up. It really is the prefix "dis" and the root word "sect"; the prefix "di" and the root word "sect" would together mean the same thing as "bisect", which would be pointless as that's already a common word. Also, it'd be spelled "disect" in that case.

That's just an American thing - you guys tend to lengthen the first vowel in any word you can get your hands on.

See Reesearch versus research, TIEtanium versis titanium, etc etc

Also, tasty there's a c in ostracising

• Registered User
RUNN1NGMAN wrote: »
RUNN1NGMAN wrote: »
Coriolis force doesn't make your toilet drain in a particular direction. Most people think it does, but Coriolis force only effects systems that are several orders of magnitude bigger than a toilet bowl.
It is amazing how many people insist on this.

I used to think this until I took a meteorology class, but I blame Mr. Wizard.

He did a demonstration where he had a tub of water with a drain plug and put it on a playground merry-go-round. He spun it in one direction, and the water drained clockwise. Other direction—counter-clockwise. I missed the part where the merry-go-round represented Earth.

De-lurk activate. OK.

This is a nit pick but I think it's somewhat important: Coriolis force certainly does act on water swirling down a toilet bowl. It arises from being in a rotating reference frame. Any rotating reference frame. The Coriolis effect from the rotation of the Earth (which has a relatively slow angular rate) just gets fucking dominated. Typically by the geometry of the basin or initial flow conditions.

You increase the angular rate, as in the Mr Wizard demo, and you can bring the dominated effect out of the shadows and into the limelight. (I didn't know that term was from lamps that actually used EXTREMELY HOT lime--calcium oxide--as the light source).

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Here's one most of you guys are probably getting wrong even as you read it: "dissect". It's pronounced like "dis sect", not "die sect", although the latter (wrong) pronunciation is gaining a lot of momentum simply as a result of how many people screw it up. It really is the prefix "dis" and the root word "sect"; the prefix "di" and the root word "sect" would together mean the same thing as "bisect", which would be pointless as that's already a common word. Also, it'd be spelled "disect" in that case.

That's just an American thing - you guys tend to lengthen the first vowel in any word you can get your hands on.

See Reesearch versus research, TIEtanium versis titanium, etc etc

Also, tasty there's a c in ostracising

Wait a second, how do other people pronounce titan then? Isn't that the root word for titanium?

• Registered User regular
Wait a second, how do other people pronounce titan then? Isn't that the root word for titanium?

It is indeed, but root words often have very little effect on pronunciation - consider logo versus logarithm, the omikron being turned into a long O in logo, but retained correctly in logarithm.