CaptainPanic

Here's an issue that's been bugging me for a while now. It seems to be expected from a man to pay drinks and dinner, and whatever else comes along (taxi, tickets to the concert) on a first date. Why is that? If we would be living in the early 1900's, I would fully understand. The man has a job, the woman was expected to take care of the household. Women had no right to vote, had worse jobs than men, and were generally seen as a lesser creature than a man. The one with the (higher) income paid the date. Makes sense. But it's 2013. We moved on. We learned from our mistakes. (Young) women nowadays often have jobs too. Good jobs. Emancipation has overcome all differences, and at least on paper, men and women are equal. So, why did the etiquette of dating not follow these developments? Are women that cheap that they forget the fight for emancipation as soon as it involves some free food and drinks? (Yes, those words are deliberately provocative).

We do feel it. We just don't notice it anymore. Take a balloon. If you want to increase the pressure in the balloon, and you push on it with two hands, it does not work. The balloon just expands where you are not pressing. The only way to make the balloon smaller (other than letting the air out - that's cheating) is to have enough people, with enough hands to push on every surface of that balloon. Air pressure is just like that: it's pressing everywhere. The only reason why the atmosphere cannot press us into something smaller is that our bodies are made up of liquids and solids, which cannot be compressed much. In a simplified way, we say that liquids and solids are "incompressible". And all the gases in our bodies, like in our lungs, is also at atmospheric pressure too.

You seem to want a website that generates reliable answers... Answers you can trust. But there are some issues with that. We participate on this website anonymously. Any data generated by someone anonymously should be regarded as suspicious. Wikipedia can only be trusted (and only to some extent) because it has many people reviewing everything. Obviously, we cannot start to review every thread and every post written. Quality control is therefore left to our readers and members. Moderators only step in when something is reported. And even then, being wrong is not against our rules. Being wrong, in fact, is a part of being a good scientist. You can only get better if you are wrong sometimes. Experts are also volunteers, and will only reply if they are interested. Maybe that's because nobody has the time to reply. We're volunteers here. If something is too complex, it takes a long time to even understand the problem. We just don't like to invest such time. Or, in my case, I often just don't have the time. We have no responsibility to answer every question that is asked. And we have no responsibility with regard to the quality of the posts written by us, or any other member. If you want to create a website where the experts have a responsibility to answer every question, and to answer it with a certain minimum quality standard, you have to pay those experts. I think you're looking at a minimum of 50,000 euro per year, to have an expert online for 40 hrs per week. I am happy to do that, btw. Of course, since I am European, I expect at least 5 weeks of holidays per year too. Ok, the costs may be exaggerated, since none of us are online 100% of the time. But my main point is just that you seem to expect a lot from a bunch of volunteers. And your solution seems to be to magically attract more volunteers. It's just not gonna happen.

Your wheel would only go up the hill on the other side to about halfway. You turn all your potential (height) energy into kinetic and rotational energy. Since you then disconnect part of that rotational energy, your wheel will not make it all he way back up.

I have to agree that a sauna is still the most likely. It's a weird sauna for sure, but it seems the most likely explanation. In the days that this was built, saunas were perhaps not so common and the people just built their own custom-made hot box? Right now, you just call your local sauna construction company (perhaps even in Brisbane?)... but 30-40 years ago, that was not common at all. My main argument why I think it's a sauna goes something like this: Why else would anyone want to build a hot box in a bathroom? But I have to admit that your photograph with the towel and the towel rack makes it look like a sauna more than you want for an unbiased opinion.

The only way that I see a Reynolds number can become negative, is when the velocity or relevant length are negative. But that just means that whoever was measuring it, started measuring from the wrong side Never seen a negative Re number before. Leni, for more feedback it is probably a good idea to link to the paper, or give the reference. (We know it might not be freely available).

Did you even read the whole thread, or did you just join our forum to troll around a bit? Anyway, you score 10 points for stereotyping and having prejudices. I am involved in this thread, so I only point to our board rules. Check especially section 2.1.c, regarding prejudices.

If you are looking for something without a flow (no water, wax, air), and no energy input (no electricity required, so no Peltier element), then you are looking at a radiator. Here's a random website which shows some passive cooling units (note: these still require the air to circulate). Scroll down to "Passive Air Cooling". Finally, even in space, radiators work. The ISS has radiators too, but I can't find a good picture now. Still, these only work if the radiators are relatively hot in comparison to whatever they are radiating at.

Spyman, thanks for that. This is the 1st time I needed to link to the rules since the new layout became effective... and they moved from top left to bottom right. It takes a lot of coffee before I would have searched in that corner. ! Moderator Note So... elnetrino... please check the rules, especially section 2.7.

! Moderator Note You probably did not mean to spam and advertise, but we have a zero tolerance policy when it comes to such links, especially if a thread is created with the apparent purpose of drawing traffic to other websites. Normally, I would add a link to our rules which say something along the lines of: "It's fine if you add a useful link to support a claim or statement, but do not create new threads to advertise particular websites". However, because we have a brand new layout, I cannot find the rules myself. Anyway, only the layout changed, not the rules... so I still removed the links. Still, because you couldn't know, we'll all pretend this didn't happen. Note that the online shops are quite capable of handling their own marketing, and don't need the help of a science forum. If any member is desperate to find any of these products, and Google somehow magically breaks down, they are advised to send a private message to elnetrino to ask for a link.

! Moderator Note Dear everybody, I have removed each and every link in this thread. In certain cases, I have replaced the link with the title and author. Please write your references according to the scientific tradition if you can. It has been used for many decades, and so far never caused any confusion. We certainly don't need to open a whole thread to link to the online book stores. Online book stores can handle their own marketing just fine. Normally, this would have been deleted as spam, but the topic is actually a nice topic. But no more links to book stores, thanks.

! Moderator Note Moontanman, Ringer, If you ask for some references, just ask for a "reference". I know it is a lot funnier when you ask for something that comes from somewhere where the sun does shine. But it is not more productive. Quoting swansont always gets you some credits here, but it may still be more productive to just ask what you want, which is a "reference". King, North TX If you are the one being asked for a reference, you must provide it. We are a science forum, not a court of law. What is good enough for a court of law is not good enough for us. Either use the scientific method, of give up the discussion. Also, laws change from country to country. Science is international. It is not allowed to make some wild speculations, and then to withdraw these as soon as someone asks for a reference. This behavior can be called "trolling", and is against the rules. Do not reply to this mod note. If you disagree with it, please use the report button at the bottom of the post, and another staff member will have a look at it.

My advice: don't let the bastards grind you down. In fact, nothing changes. If you were going into the sciences for your own personal gain, then you made a wrong choice anyway. You're not gonna get rich being a scientist. So, while it is indeed sad that the world around the scientists is a lot nastier than you thought last week, this is happening outside your field, and doesn't / shouldn't influence you. The only relevant piece of info is that the job market is not as good as you thought. And if that were true only in the sciences, then this could be a reason to change your mind. But it's crisis everywhere.

I propose we set up a new thread, because I think we're going off topic. Since the thread drifted off topic quite slowly, I cannot determine where it exactly happened. Also, because I am involved in the thread, I am officially not allowed to moderate anything here. Does it make sense to ask one of you (Arete or CharonY) to summarize this properly and make a new thread? ! Moderator Note In this thread, we will now focus on the progress of The Peon again, as was intended in the opening post.

I'm a chemical engineer. I am not working in the biotech, but I do sometimes work with the biotech. All I know is that companies are still actively searching for people. It's not like in the early 2000's, when companies went mad to attract someone. But it is also not the case that for every opening they get loads of applications. Sometimes companies struggle to find a suitable candidate. I do see emails sometimes from other companies trying to encourage people in a particular network to apply for a job with them - and these are mails sent to people who generally speaking already have a job (like me). Anyway, I would much rather be on the job market with a biotech diploma than without it... If you take both income and job satisfaction into account (and you should), the investment in a study in biotechnology will certainly have a payback time.

True, but only true for subsidized research. Our governments try not to spend more than they get contrary to the USA where spending can be twice as much as the government revenues. But now I am going off topic... For example in the Netherlands, there is still a shortage of scientists/engineers in the exact sciences. I am sure that a degree in biotech would get you a job soon enough here. But it would probably be in a commercial company, not at a research institute or university. The expectation is that this shortage will only increase in the near future, because the baby boomers are all retiring. I can only find sources for this claim in Dutch, but just in case you don't believe me, here's one. And here's one which even claims that there will be an increasing need specifically for biotech (again in Dutch, sorry).

I personally think that you ask for too many units. It makes more sense to give a proper explanation (in a piece of text) what something represents. The sheer number of possible dimensionless numbers is mind boggling. I would not want to design an "SI system" for that. But a proper description is essential, and in many cases also provided.

Of course: if you take 10% of horizontal measurement over another horizontal measurement then it's a different thing altogether. Still dimensionless though.

10% slope is dimensionless, but it is perfectly OK to write it as 10% m/m (meter per meter), although it might confuse the hell out of an unsuspecting construction worker... In fact, in chemical engineering, we often calculate the fraction of a certain chemical in a mixture. A well known fraction (and very yummy fraction) is the percentage alcohol in beer. It is quite a big difference if we are talking about 5% weight/weight, or 5% volume/volume or 5% mol/mol. This is why on beer bottles it is specified which kind of percentage we're talking about (usually %vol/vol, also written as %vol). Now, when it comes to slopes of a hill, there is little doubt that you're talking about length/length... so specifying it is a little less important. And now for something completely different Arnaud Antoine ANDRIEU, your link seems 100% (information per information) off topic. It should me mentioned that in the case of 100%, the specification of which kind of percentage you're dealing with is usually unimportant, because 100% is the whole thing no matter what you're talking about. Anyway... your post doesn't make any sense to me.

There are signs that the climate is causing weather to become more severe (someone invented a new word, and called it 'global weirding'). That means more damage to houses. And that means that you need to pay more to your insurance company. The funny thing is that everything you say is true, but although you don't literally say it, you seem to suggest that humans are not influencing the climate, and CO2 has nothing to do with it. Humans, who have changed the surface of almost the entire landmass of the planet, and who have significantly increased the concentration of multiple gases which are responsible for the absorption of infrared light, and who also emit large amounts of particles (soot, etc) - so much in fact that on a day when there were no airplanes in the USA, the difference was immediately measurable. It sounds like you suggest that those humans have nothing to do with the climate. It's weird how words can sound when chosen carefully. Anyway, I think that the above is nonsense, and if you indeed claim that humans have nothing to do with any changes in the climate, then I would like to have some citations and clarifications please.

I would google for it, so I don't see any point in doing that for you. I am no ion-thruster-expert, and I have no secret sources of information So, sorry... but I don't have anything more myself.

What do you mean "in any form"? I only know one form of static electricity, and that's static electricity... but maybe I don't understand your question.

You are not entirely wrong, but for the most part you are. (I'm not trying to make fun of you here). Orbit There is one good reason why rockets go as fast as they do. They need to get into orbit (wikipedia). In order to get into orbit, you need such a high velocity that the gravity of the planet Earth cannot pull you back to the surface. This is why satellites and spaceships can stay in orbit without burning their rocket engines once they are up there. The velocity needed for a Low Earth Orbit (often abbreviated "LEO") is about 7.8 km/s. Note that the rockets go straight up at first, but then bend their trajectory to go nearly parallel to the earth's surface. They need to get up to 7.8 km/s in a circle around the earth, so parallel to the surface. But... the further away from the earth you get, the lower the velocity required to stay in an orbit. If you are at 35800km altitude, you only need to go 3.07 km/s. This is called geostationary orbit. And there are orbits where you only need to go as little as 500 mph to stay in orbit. But those are at a very large distance away from earth... and your spacecraft would have to keep going at a steady 500 mph for multiple days to get there... burning its engines all the time! Getting into space is maybe not the hardest part. The most difficult is staying there. Straight up (no orbit) There is a different way to look at this. The escape velocity you need to get away from planet Earth is about 11 km/s. At such a huge velocity, the gravity of earth is not strong enough. But if you get away from earth far enough, the gravity just doesn't act on your spacecraft anymore. At a certain distance, 500 mph is sufficient to keep going. However, that is at quite a huge distance. And again, until you get there, you need to keep burning those engines. Conclusion Basically, in both cases, it is easier to get up to an orbital velocity, so that the Earth's gravity stops slowing you down. And if you want to get away from the planet altogether, you can then slowly increase your velocity (while you are still in orbit). And this is exactly what is done sometimes: a big rocket to get to orbit, and a puny little ion thruster to increase the velocity after that.

You must be a manager or a boss somewhere... p.s. I see it's your 1st post ever here, welcome to the forum

I agree with ajb. On the surface, there are many cool science/engineering topics, which are often found in popular scientific programs, articles, websites and magazines. They usually deal with the results, but not much with how the results were achieved. For example, building a new bridge: they will show the construction and the finished bridge (and the grand opening). They don't show the team of engineers who were doing calculations for months or years, and who were designing many different options. So, I guess you have to ask yourself: are you interested in the popular science and popular engineering, or do you want to become a scientist or an engineer? To achieve the former: following the popular scientific sources of information is enough. It will be a hobby for you. To achieve the latter: you will have to build up a strong background in maths, physics, and possible chemistry, biology or something else. And then you have to learn how to apply that to your chosen field of science/engineering. And the recommended way to do that is to finish your school and go to a university. There isn't really a shortcut, I'm afraid. There is a middle way though. We all need programmers. Scientists and engineers often use specialist computer programs. Those are built by a team of scientists and good programmers. I have no idea how you can get such a career as a programmer though. The risk is that you get close to the science, but that you instead end up in the IT department of a large company... fixing people's crashed computers. Be sure to apply not just at the right company, but for the right job too, if you follow this path.