CaptainPanic

Indeed. The qualifiers are absolutely necessary. As I wrote in the other thread, what you have to look at is a reaction. Unless a single component will react with itself, you will need to describe the environment in which the component is present... and the pressure, temperature, possible catalysts, other components which interact (solvents, even inhibitors). In other words: to be able to say something about reactivity, you pretty much need to describe the entire experiment...

Flow through an orifice is what you want to study. So, the swinging will cause pressure changes. When the bucket is most left and most right, then the gravity plays a smaller role (and if it would be swinging up to 90 degrees it's basically in free fall, and the gravity plays no role at all). When the bucket passes through the lowest point, it will experience more than the standard 9.81 m/s2, due to gravity and its circular motion. So, how does the force change as a function of the position? How does the flow change as a function of the force (probably better to express the force as a pressure at the bottom of the bucket).

National geographic has a show (a series of documentaries) which are called "My brilliant brain". It is about people who are considered geniuses. It explains their capabilities, and attempts to explain what's the differences between their brains and the "average" human brain.

Bees, if they could make plots would also use 90 degrees. Anyway, if you are really-really convinced that bees would be able to do maths the bee-way, then please move on to translate the theory of trigonometry into this 120 degree world. Humans build staircases which do not use perfect 90 degree angles for the vertical sections. This is to increase the surface where you can put your foot, to be able to have a steeper staircase without losing your footing. I really don't understand what a staircase has to do with the scientific and mathematic meaning of the perfect right angle. Until now, all you have been saying is that it's possible to make projections .

I am looking at a large wind turbine from my office window. The blades rotate once every 3 seconds (approx.). The blades about about 50 meters long. The tip of the blade therefore travels: distance = 2*pi*r = 2*3.14*50 = 314 meters in 3 seconds. That equals over 100 m/s... I can tell you that the wind here is definitely not 100 m/s (I really wouldn't be sitting here). So, yes, blade tips definitely go faster than the wind. The concept is quite easy I think. The wind hits the blade. The blade has a shape which deflects the wind to the side. Since action=reaction the blade itself will move the other way... so it starts to spin. I am not sure that lift has much to do with it. Why would a blade need to generate lift, and in what direction would that be? Forward? It's a stationary machine. Although aerodynamics is definitely the right field to study the wind turbines, not all aerodynamics has to do with lift... But there is no reason why a blade tip would not be able to go faster than the wind speed. Make a force balance, and try to find the force that will slow down a blade. In a well designed wind turbine, that force is the gearbox and generator. If you let a windturbine spin freely, and thus let it go out of control, the blade tips might even break the sound barrier.

You realize that the police aren't trained and are not expected to be able to answer your question, right? The questions asked don't have to make sense. The answers given may be 100% correct and true. It just has to seem suspicious... and you're guilty. Tomorrow's news: "Enormous increase in corruption by police officers". I wonder if the people whose 26000 was taken even got a receipt... it may have just disappeared. [sarcasm]I'm so glad that our world has become so much safer over the last years, with the increased power for police and the enormous increase in security measures worldwide.[/sarcasm]

This thread (click) deals with the concept of "reactivity". At the moment I write this, it's just 15 threads down in the forum index. Bottom line: "Reactivity" is not a very useful concept. You already punched your first hole in it, and as you learn more about chemistry, you will find out that "reactivity" is a concept which is a bit useless... And as hermanntrude already said - unfortunately for people who just start in chemistry, it's all a bit more complicated than that. But don't be discouraged. Chemists also often have no idea what's really happening *hides in a corner*

Sometimes morality goes against survival. Then what? Please note that I agree with the general idea. We should help each other, not kill. Feed each other, not let others starve. Treat each other with respect, even when you disagree with each other. Morality is important, but when you're really hungry/thirsty, or somebody is threatening to kill your family, it is not so important anymore... Luckily the people who read this are the ones who should stop using all the riches of the earth - rich people are the ones who need to take initiative, and start behaving morally correct. We rich people (and anyone with internet access is part of the richest 50% on earth) need to give up, so that the poor people can have a bit more. And that's kinda hard, isn't it?

90 degrees is not a coincidence. 90 degrees is also no human invention, and has little to do with how we like it, feel about it or felt about it 5000 years ago. 90 degrees comes from 180/2 degrees... and in that light it's not so amazing. 180 degrees is a straight line, and no matter what kind of thing you invent, a straight line is always straight, and if take a point on that line, and you want to make a second line through that point and have an equal angle to both sides, then the perpendicular line is the one you will find. That's just simple maths, not psychology. Incidentally, the 90 degrees is also found in nature: It is the angle between a flat surface of water and the direction of gravity. (Agreed, there is some rounding off here - the earth is not exactly round). Also, right angles occur in many places in physics (for example the Lorentz force - it wouldn't become 85 degrees if we changed our definition).

That looks like "Guilty until proven not guilty"... which seems like completely the wrong way around. But it is in line with all developments worldwide.

At that altitude, there is a vacuum. If you put a pipe down into the atmosphere, then there is still a vacuum at the top of the pipe. Then you can turn on the pump, but you're pumping a vacuum. Now, we know that there is in fact always a molecule around, so you'll pump something. But it will be so horribly inefficient to compress the gas to something breathable that it's simply a bad idea. Secondly, the upper atmosphere (ionosphere) contains different gases than the lower atmosphere, so you might have to reconsider if you even want to breathe it. I believe that there is only 9% O2. The rest of the oxygen is bound in some other components. Third, such a long pipe into the atmosphere will certainly make the spacecraft crash into the atmosphere.

The Andromedans allied themselves with the plant-life? Plants will stop making oxygen? I always thought that plants were suspiciously quiet the whole time.

I find that TV generally aims at an audience with a relatively low intelligence (sorry to all those who like TV). Good documentaries are rare... and most are boring. Youtube sometimes has some decent documentaries, but often you'll have to search for a while until you find a good one. Recently I watched a movie (or actually a lecture) called " ". It's about the universe when it was still quite young. For the rest, I always loved Sir David Attenborough's nature documentaries... and if I'm linking to youtube anyway, let me give you a link to a short 3-4 min movie about the Lyre bird.

why not? it may seem more simpleminded and easy to do that, more art than thought, but thats still engineering. engineering is making things right?, so, why would that not be considered engineering? and architectual engineering is more than just drawing on a peice of paper anyways... I don't know As I wrote: in the Netherlands, architects are engineers. I don't know if it's true that they do a lot less calculations and know less of math, but among the other students at the technical universities, it's rumored that architects have trouble in maths, and are generally more artists than engineers... Personally I never saw the work of an architect (although I obviously see the results every day: buildings). First of all: I'm not working in construction, or even in architecture. I'm a chemical engineer and my work is to make chemical factories run clean, efficiently and profitable (and I work for sustainable energy and processes)... therefore my views here might require a doublecheck. My view was that the architects design a building on paper. Then a civil engineer checks how to actually construct it (what materials, and how strong it all should be - also still on paper/computer). I thought that a civil engineer therefore does more calculations. Civil engineering is also a complete university study (BSc + MSc, and optional PhD). This does not mean that an architect doesn't do this type of calculations too. I believe that nowadays it is common that the beauty and functionality go hand in hand. Something that looks like a decoration is actually an essential part of the construction. This logically means that the fields are moving towards each other. You know - when you're looking for a study, the whole world is in categories "Civil engineer", "architect", etc. Then when you finish the studies, and you start working, you find out that it's divided as clearly as you think. I'd suggest that you make sure that you learn all the maths you need - and accept the consequence that you might not do as many drawings (art) as you might want. Then at a later stage, you just need to find the perfect job which has the right balance between nerdy calculations and art/design (which may or may not be hard, depending on your own qualities). Finally, I'd like to say that there is only 1 reason why maths is as well developed today as it is: and the reason is physics. For a large part physics = maths. So if electrical engineering has physics in it, it automatically has maths. Also, the maths you'll need in other engineering fields are always applied to solve physics problems - engineers apply maths all the time to solve physics / chemistry / thermodynamics problems (and btw, all those fields have large overlaps - the real world doesn't have the nice categories).

Two, three fields spring to mind: - applied maths was one of the faculties at my university (edit: which was a technical university, educating only engineers). - aerospace engineering in general contains lots of maths (a lot of funky aerodynamics, but other fields in that study are also full of math I think) - systems control (which can be studied in several fields/faculties: chemical engineering, aerospace engineering to name a few) The "civil engineer" is the one who makes sure that things don't collapse. So this is a field where engineering meets architecture. Because drawing a nice building without any calculations doesn't count as engineering? I think you already answered the question yourself. In the Netherlands the architect is an engineer. Hope that helped. Ask more if you want. We're all here voluntarily to answer good questions such as these. I'm sure others will also add their views.

2. Cyclo-alkanes are products from the oil refineries. For some part, these are already formed in the crude oil... although aromatics (with a benzene ring) are more common. Some heavy components (stuff that resembles asphalt) of the crude are quite useless, so these are sent to the crackers. The Catalytic cracker breaks up molecules. These are then radicals which are able to recombine. Sometimes this forms a ring structure. It's all quite random and violent I believe, although I'm sure that lots and lots of research has been done to improve the catalysts and to influence the products. Some of the ring structures are cyclo alkanes. It's possible to add hydrogen to the cracking process (it's then called a hydrocracker). This will reduce the amount of double bonds, and also the amount of rings that are formed. You can also hydrogenate benzene or some cyclic alkenes (olefins). This is also why a component such as cyclohexane is so cheap, I guess. It's a large scale bulk product. There exist also methods to produce specific cyclo-alkanes, but that is something which you can better search for on wikipedia.

I think we all agree that polypeptides are peptides. Since some people suggest that peptides are indeed polymers, these people are suggesting that two amino acids that are connected through a single peptide bond are not a peptide?? How about that? I believe that some peptides are polymers, but not all peptides are polymers (2 monomers is not enough to call it a polymer).

Dutch newspapers were all positive this morning about Obama's message. It's said that the Iranian government welcomes the latest message. Obama also wished Iranians a happy Nowruz, which is the Iranian New Year (beginning of spring). I think that such simple forms of politeness really make a big impact. Behaving, using simple manners and being polite even to ones rivals is an excellent example to the entire world. And it doesn't necassarily mean that Obama is a softie. You can be very hard, yet polite. Dutch newspapers about the message from Obama to Iran: link 1, link 2 (both in Dutch). (I know not many will read them, but I prefer to provide a reference when I quote from a newspaper)

In my particular field (chemical engineering, which sometimes borders on mechanical engineering) I do calculate all the time... but very often it's just simple stuff. I am not solving differential equations day-in-day-out, although there are fields in chem. eng. where you need this every day. If you hate math, avoid process control systems. And obviously I had to struggle through the courses back at university. The simple truth is that in chemistry, we often do not have sufficient data to even bother with the complicated formulas. It's all approximations and rules of thumb. But if you even don't want to grab a standard calculator, then perhaps you're not in the right study. As for memorizing functions - why memorize then when they're written down in a book? I never understood the concept of memorizing - it's just not necessary since people learned how to print books Besides, there are too many formulas and functions to memorize them all (imho).

It might also make it easy to have a dedicated battery recycling center, which needs a different technology and possibly has different hazards than a scrapheap. More advantages.

I guess that there's a small army of lawyers that work full time to resolve disagreements like this then I know of so many disputes regarding import tax, concerning every-day goods and services. It seems that regardless of rules and regulations, there is always somebody complaining about them too.

You can't let banks fail, I agree. We need some money transfer institutes where you can store and borrow money. I'm not so sure that it should be the central part of our economy though. Banks should just facilitate the economy, not form the main part of it. But what would happen if you can prevent them from making profit from now on? (Nationalize the whole system, make it a public system)? It is quite radical, and I'm not sure that it would work, but it would stop the short-term thinking that was partially the cause of this crisis. I'm an engineer, not an economist. But wasn't money once meant to represent physical things? How can stocks and currencies fluctuate so much as they do? Why did the USA become 20-30% cheaper in a matter of months (for people with euros )? The Americans surely did not lose 30% of their goods. I fail to understand it, and I'm arrogant enough to say that this could be a sign that the system doesn't make sense rather than me not understanding enough of economics.

Ahh, I see. But doesn't that mean that apparently the US and EU have some trade agreement about the free market for airplane sales? There exist many markets which are not opened up, and where trade barriers (import taxes) are still in place, or where government subsidies influence sales. The entire food market is one example. Why else do Europeans eat European food (when it's produced at half the price in other continents)? The sustainable energy market is another one. And anyway, I believe that we're talking about the construction of infrastructure here, which is often a national business.

You will have to measure it, model it, discuss it and then accept that there is still a (small) error. Intermolecular forces are hard to measure. Because there exist so many chemicals in the world, there is a big chance that there is no data from measurements. I believe that models such as the UNIFAC model... UNIFAC models interactions from group contributions. Did that answer the question? Please post a more detailed question if you want to know more.

Umm... Rules / regulations for pharmaceutical products are incredibly strict. I would suggest that you study the rules and regulations so that you can find out what you can, and what you cannot do for making that cream. Be prepared to spend a lot of time on reading the regulations - these are books, not pages full of info. You can use the formulation of other creams to get an idea (and you can use the same ones if they are not patented and if you can find out the formula in the first place, which is unlikely). But whatever you do, you won't be able to put your cream on the market without a lot of testing. So, you probably need more than just 1 person to help... and you'll need a couple of years of testing. I'm not sure if you realize the magnitude of your project here.