Bender

Why? In a lot of parking lots, I expect the air to be hottest near the grond. I can't really find proper data apart from the fact that above 1 foot all air has more or less the same temperature.

Why not just use the ventilation system already present in the car and add a smaller fan connected to solar panels?

The potential gain does not outweigh the additional cost. In this case, nobody would buy an ugly, expensive car with solar panels and fans in the roof, because leaving a baby in the car "will surely never happen to them" anyway. To put in some figures: On average, 38 children die this way every year in the US. In 2015, 938 children died in motor vehicle accidents in the US. So it makes sense to put 25 times more effort into preventing the second category. But if it really bothers you, nothing prevents you from putting a fan in you roof and installing a solar panel on top. It isn't even that difficult to do yourself. I'm not really sure that it would be 100% effective, though. The air can only get as cold as the surrounding air, possibly heated by blistering tarmac on a parking lot. Still a considerable improvement, obviously, but a child left for hours under those conditions could still die. I don't think this is entirely fair. Why would they sell a car that nobody will buy? An afterthought: wouldn't such a system encourage parents to knowingly leave their children in the car "only for a minute"?

It could have started out as a side effect of creativity and evolved further to impress the other gendre. The bowerbird is a clear example of this: https://en.m.wikipedia.org/wiki/Bowerbird

Why do you think that? In non-religious schools in Belgium, children get a morality/ethics/reflection course instead of the religious course.

The name is wrong, because it is not a theory, but an incoherent collection of untestable hypotheses. I'm no expert at all, but there might be as much string theories as there are string theorists. The problem is that there is no data to make all the countless choices required to build a mathematical model on. I read a quote once stating that different string theories where so far apart that the respective physicists could hardly understand each others papers. None of that means that it is pseudoscience or without value. What is required is testable hypotheses and experimental data to weed out the wildgrowth of hypotheses. Examples would be the discovery of supersymmetric particles in CERN, or the possibility of putting large scale objects in superposition.

I quoted the book. It isn't a quote in the book. In the US it is required to be biased towards religion to get elected. That is a clear example of how religion plays a much bigger role in the US than in a lot of European countries where it would be unthinkable for someone to get elected after publicly speaking about God.

I care because it is an educational textbook which is otherwise void of opinion. When I read a paperback about physics, I know I'll encounter the personal opinion of the author. In a book aimed specifically at education, if there is topic discussed which is open to opinion, I would expect different sides of the discussion to be represented. The fact that the president can speak the words "God bless America" without getting impeached, is a hint. I thought it is even possible for a religious leader to perform a legal marriage, which, if correct, is a violation of the separation of church and state. Otherwise creationism seems to be a much bigger problem in the US, but there are definitely regions in Europe where that is an issue as well. Personally, I hardly know anyone who attends church, but I'm from Belgium, where only 33% says their religion is important vs 69% in the US. This list provides some actual data. The top of the list (religion not important) is definitely dominated by European countries, with Australia, Cuba and some Asian countries mixed in. There are definitely European countries that are more religious than the US. They seem to be concentrated in the south and southeast of Europe. I found it interesting that in Israel only 51% of the population says their religion is important.

Ultrasonic levitation is great to bend paper or shoot up small pieces of foam: https://www.youtube.com/watch?v=dyUHoAT0x9A You can even feel a slight sensation when you put your hand over it. You cannot lift a car with it. Suppose you lift a car of 800 kg with an array of ultrasound generators with an area of 8 square meters (in other words, all the area under the car needs to be used effectively). You now need 1000 N/m² or 1000 Pa of air pressure (very conservative simplification). This is almost twice the pressure a jet engine squirts out at a distance of 1 m, and equates to more than 150 dB. Anything above 140 dB can cause instant nerve damage in your ears, and I doubt not being able to actually hear it is going to change that much. On top of all that, you cannot recuperate the energy blasted out. It is all pure loss, and you're not even moving yet, only hovering. Because of the conservative oversimplification of how ultrasound can exert forces, the actual situation will be much worse. It is also a mystery to me how you would go about creating, maintaining and containing a plasma powerful enough to levitate on without it damaging the car or the road. High energy plasma is in general not very friendly to its environment. (To be honest, I have no clue how you would go about creating, maintaining and containing the plasma at all, but that issue has already been raised by others).

Unless you are staring at UV-light or higher energy photons, the individual photons can't hurt your eyes, because they cannot ionise. A large number of them can heat up your retina and cause thermal damage. The fact that the lens of your eye focusses the energy on a small spot increases the problem. For this it doesn't matter if you consider them photons, waves or field excitations.

The only instances I can remember actually closing the seat is to be able to put something on top or to stand on it. Worrying too much about bacteria can be worse for your health than the actual bacteria . Squatting above the seat is also worse than sitting on a dirty one. Just wash your hands and you'll be fine.

Sure.

That makes no difference. They can cancel each other out when parallel as well. Angular momentum doesn't have a position, only an orientation.

The math is really very simple: [math]F_1=-F_2[/math] Repeat for every force the spacecraft exerts on itself [math]\Sigma F=0[/math] in other words: no thrust. Technically, sending out electromagnetic waves gives a tiny bit of thrust because of its tiny momentum, but you'd be better off just sending the waves backwards.

I can help you out in that respect, since it is quite simple: L-L=0 With L the angular momentum. Both angular momentums cancel each other out, and the resulting angular momentum is zero. Without angular momentum, no gyroscopic effect.

You're reading to much into this. I never claimed that parents can't teach their children about religion. I have no problem with it, as long as their basic right to proper education is not violated. Besides, the children also have freedom of religion, which can only be guaranteed by at least teaching them about other religions.

Apparently, males don't like fatty or muscular butts, but a 45 degree angle of the lower spine.

The concept of public schooling as welfare made me shiver, but I think we are getting too far off topic. We also seem to be talking next to each other, since I only know US schooling from Hollywood and most of you clearly have no clue about schooling in Belgium (I guess we have "heavily government-dependent" private schools, which are functionally public schools, but no independent private schools). I think children's rights have priority over personal freedoms of the parents. Even over freedom of religion (to attempt to steer this back to topic). About the suggestion that home schooling protects from suicide (slightly on topic, since home schooling often seems to be religion inspired): please check the facts. Suicide among homeschooled children. General youth suicide rates. While both studies are difficult to compare, and my Google-Fu isn't providing me with anything better, both give an 8% for children attempting suicide. 43% of the homeschooled children had considered suicide while 24% of the general adolescents had "seriously" considered suicide. I hope you are considering the fact that there are bullies in youth movements, in college/university and in any future jobs, before you send your children out there without any preparation. Bullies will happily pick out easy victims without defenses who like to talk about their mommy because they haven't seen anyone else all week.

You are right. I've learned something today .

Perhaps you could. Perhaps you even have the pedagogic and didactic skills to pull it off. Do you claim that everyone (or even a large percentage of those) interested in home teaching has all those skills? You still cannot teach them social interaction skills. Where do you get that number? They must be using a strange definition of "private schools". Possibly they refer to schools not explicitly organised by the government, but these still get their funding from the government, teachers are considered government employees and paid a salary by the government and they have to meet the "end requirements" set by the government. Unless I'm completely mistaken in how private schools in the US operate, there is very little similarity.

Magnets can slowly degrade over time, but this takes many years and is not really related to how often it pulled on a ball. In fact, while it is pulling on a steel object (or another magnet), the degradation happens slower. More on e.g. this link. I remember from school that they told us always to store magnets with a piece of steel attached to close the magnetic field lines, and there is certainly some value in that, since it keeps the field aligned rather than it attempting to turn back on itself. It is also in a lower, and consequently more stable, energy state.

When trains are upside down, there are bigger problems.

We have no private schools. So, yes, I have visited public schools recently. At least a dozen different public schools this year. There is no contradiction. In a place with good private schools and poor public schools, I would probably send my children to the good private schools. I still prefer a system with no private schools. My point is that a country with no private schools apparently can have better (average) results then in a country that has both public and private schools. As evidenced from the examples given, there seems to be huge quality difference in the US both in private and public schools. I guess I was thinking about private schools were if a teacher fails a student, the teacher is to blame, because the parents payed a lot of money for their children to get a degree. That is probably only true for a subset of private schools. I don't care for home teaching at all, since the right of proper education is not guaranteed at all. No parent is qualified in all the different subjects, and I find the lack of social interaction disturbing.

I didn't say you shouldn't send your children to a private school; I said there shouldn't be any private schools. If rich parents had to send their children to public schools (like they have to do in e.g. Belgium), they would be more likely to agree with more tax money being spent on public schools. More good students would go to public schools, which automatically increases the level of those schools for everyone; and good teachers wouldn't be lured away from public schools. An additional advantage is that children play with other children of all layers of society, rather than only the elite. The survey mentions that it compensates e.g. for race/ethnicity, but it says nothing about the level of education of the parents. If they didn't compensate for that, it is worthless to compare the two, as illustrated by this report. You could also look at the international PISA tests. There are probably other countries where there are only public schools, but at least in Belgium everyone goes to a public school and it scores higher than the US on all three categories.

And since the flanges are longer than they are wide, there is no risk of the wheel slipping sideways in the small slot.