Snopes - 1

Urban legends can be interesting. Some of them are plain funny, others encompass deep substance and a few are actually quite inspiring. Even if they are not true, some of them are just lovely to read, giving new satisfaction each time it is being read over again.

I selected 4 good ones from this section.

http://www.snopes.com/college/exam/exam.asp

EXAMS:

Introductory Chemistry at Duke has been taught for about a zillion years by Professor Bonk (really), and his course is semi-affectionately known as 'Bonkistry'. He has been around forever, so I wouldn't put it past him to come up with something like this. Anyway, one year there were these two guys who were taking Chemistry and who did pretty well on all of the quizzes and the midterms and labs, etc., such that going into the final, they had a solid A.

These two friends were so confident going into the final that the weekend before finals week (even though the Chem final was on Monday), they decided to go up to UVirginia and party with some friends up there. So they did this and had a great time. However, with their hangovers and everything, they overslept all day Sunday and didn't make it back to Duke until early monday morning.

Rather than taking the final then, what they did was to find Professor Bonk after the final and explain to him why they missed the final. They told him that they went up to UVa for the weekend, and had planned to come back in time to study, but that they had a flat tire on the way back and didn't have a spare and couldn't get help for a long time and so were late getting back to campus. Bonk thought this over and then agreed that they could make up the final on the following day. The two guys were elated and relieved.

So, they studied that night and went in the next day at the time that Bonk had told them. He placed them in separate rooms and handed each of them a test booklet and told them to begin. They looked at the first problem, which was something simple about molarity and solutions and was worth 5 points. "Cool" they thought, "this is going to be easy." They did that problem and then turned the page. They were unprepared, however, for what they saw on the next page. It said:

(95 points) Which tire?

Assuming the car had four tires, they had a quarter chance of 'getting it right'.

~~~

Just before Christmas a college professor read the following on an examination paper: "God only knows the answer to this question. Merry Christmas."

Across the paper the professor wrote: "God gets an A, you get an F. Happy New Year."

~~~

The following concerns a question in a physics degree exam at the
University of Copenhagen:

"Describe how to determine the height of a skyscraper with a barometer."

One student replied:

"You tie a long piece of string to the neck of the barometer, then lower the barometer from the roof of the skyscraper to the ground. The length of the string plus the length of the barometer will equal the height of the building."

This highly original answer so incensed the examiner that the student was failed immediately. The student appealed on the grounds that his answer was indisputably correct, and the university appointed an independent arbiter to decide the case.

The arbiter judged that the answer was indeed correct, but did not display any noticeable knowledge of physics. To resolve the problem it was decided to call the student in and allow him six minutes in which to provide a verbal answer that showed at least a minimal familiarity with the basic principles of physics.

For five minutes the student sat in silence, forehead creased in thought. The arbiter reminded him that time was running out, to which the student replied that he had several extremely relevant answers, but couldn't make up his mind which to use. On being advised to hurry up the student replied as follows:

"Firstly, you could take the barometer up to the roof of the skyscraper, drop it over the edge, and measure the time it takes to reach the ground. The height of the building can then be worked out from the formula H = 0.5g x t squared. But bad luck on the barometer."

"Or if the sun is shining you could measure the height of the barometer, then set it on end and measure the length of its shadow. Then you measure the length of the skyscraper's shadow, and thereafter it is a simple matter of proportional arithmetic to work out the height of the skyscraper."

"But if you wanted to be highly scientific about it, you could tie a short piece of string to the barometer and swing it like a pendulum, first at ground level and then on the roof of the skyscraper. The height is worked
out by the difference in the gravitational restoring force T =2 pi sqr root (l /g)."

"Or if the skyscraper has an outside emergency staircase, it would be easier to walk up it and mark off the height of the skyscraper in barometer lengths, then add them up."

"If you merely wanted to be boring and orthodox about it, of course, you could use the barometer to measure the air pressure on the roof of the skyscraper and on the ground, and convert the difference in millibars into feet to give the height of the building."

"But since we are constantly being exhorted to exercise independence of mind and apply scientific methods, undoubtedly the best way would be to knock on the janitor's door and say to him 'If you would like a nice new barometer, I will give you this one if you tell me the height of this skyscraper'."

The student was Niels Bohr, the only Dane to win the Nobel Prize for physics.

Education is not about "Teaching people how to think", it is about teaching them how to learn.

~~~

An economics professor at Texas Tech said he had never failed a single student before but had, once, failed an entire class. The class had insisted that socialism worked and that no one would be poor and no one would be rich, a great equalizer. The professor then said ok, we will have an experiment in this class on socialism. All grades would be averaged and everyone would receive the same grade so no one would fail and no one would receive an A. After the first test the grades were averaged and everyone got a B. The students who studied hard were upset and the students who studied little were happy. But, as the second test rolled around, the students who studied little had studied even less and the ones who studied hard decided they wanted a free ride too; so they studied little... The second Test average was a D! No one was happy. When the 3rd test rolled around the average was an F. The scores never increased as bickering, blame, name calling all resulted in hard feelings and no one would study for anyone else. All failed to their great surprise and the professor told them that socialism would ultimately fail because the harder to succeed the greater the reward but when a government takes all the reward away; no one will try or succeed.

A Possible Ultimate Question

Recent news have announced that Stephen Hawking believes that creation did not require a creator, going against modern conventional christian culture. Physics have toppled many theories and we have to embrace that fact that it should not be treated second place to religion in 'the search for truth'. Who is to say that these religious beliefs are not as 'untruthful' as science, considering that religion is molded by humans, therefore leaving room for biasedness and unreliability of sources.

The battle between creationists and evolutionists is still not over today. There is sufficient scientific evidence today to say that evolution is a probably phenomena that created the variety of organisms we see today. After all, we don't see odd otherworldly creatures springing out in the wild nowadays. From my point of view, since evolution is a more logical process to happen, it is more likely to be true, though I cannot rule out the possibility that creationism is 'more right', for someday logical argument might be presented about creationism.

That was a controversial example. One thing we cannot deny is that the Earth moves around the sun, not the other way round. To be extremely precise, in fact neither moves around the other, as gravitational attraction is mutual and motion is relative. However this was an idea banned in ancient times. People preferred to believe that the world revolved around them. A perfect example of how religion is not foolproof. Created by humans, subject to errors. But the best we can do would be to think logically and listen to our conscience and observe 'the truth around us'.

(For the sake of argument again you can say that our conscience is a dimensionless concept instilled into us by aliens in order to trick us and our logical system is actually entirely flawed and yet we do not spot the paradoxes beneath them because our mind is not so great to comprehend them)

But look at the title, this post isn't supposed to be about searching for truth. As I was thinking about Stephen Hawking on the bus quite some time ago, I realised that I came to a very fundamental question.

How is the existence of existence justified?

Based on definition, we live in a world that exists. Many people believe that this world originated somewhere in the distant past, and so do I. When I say the world I don't just mean the universe. Maybe clusters of Universes, from the beginning to the end of time.

If we believe in a creator, then who created that creator?

If we do not believe in one, then there must be a process that make this world work. Maybe a process which causes the world recycle itself time after time spontaneously? Then isn't that process 'something'? What created that process?

Why does something exist, rather than nothing?

Soon we realize that this question is itself a paradox. Any attempt to answer that question will result in a contradiction.

It's no use thinking about it, and it serves no purpose, neither would the world be made a better place if you know the answer.

It's just a thought.

World of Science - Aerodynamics - Part 7

I have nothing much to write about the last few lessons. For the last last lesson, the lecturer from NUS talked about start and end vortices induced by airfoils, and how these cause wings to fly. Honestly, it does not make a lot of sense to me, and I have came to a realization that I do not understand how aeroplanes fly based on this circulation around the airfoil explanation completely. However, one thing is for sure, that is I do not know how airplanes fly. Sounds contradictory? Let me elaborate.

When I was really young, I thought that airplanes fly because air hit the wings and get deflected downwards (partially correct). I mean like balls bouncing off the wings and creating a upward momentum. I thought this, because of the phenomena that when I fold the back of the wings of a paper plane up, they tend to go upwards. So I just thought that the 'balls of air' will push the wing and cause the plane to pitch.

However I later found out that a fluid doesn't act like a solid. The path of a fluid curves even before hitting the obstructing surface. So upon learning Bernoulli's Theorem, I thought I knew how wings can fly. This explanation, I thought always correct, and perhaps many others is in fact a misconception: Air flowing above the airfoil takes a longer time to reach the end, while that flowing below the airfoil takes a shorter time, so the air above has to flow faster, thus causing a lower pressure on top.

The flaw in this explanation lies in which, there is no logical explanation as to why the air on top should meet the air below at the same time, so there is no reason for it to be faster.

I found this website in an attempt to understand how wings work. I don't quite get it still, but it is an improvement compared to the wrong stuff that I always thought was correct.

So now I have now upgraded from not knowing what I don't know, to knowing what I don't know.

Next, the lecturer talked abit about animal flight, something I have already listened to during the NUS physics camp. Exact replica. He showed us a few high speed camera videos of birds flying. Some think that its funny, I think that it's really impressive to see stuff like hummingbirds flapping their wings in slow motion. And albatrosses crash landing. And the eagle's precise landing by diving below its eyrie and swooping up again, converting its kinetic energy all into potential for a steady landing.

The following week was a lesson about aircraft stability and control surfaces by Dr Robert Goh from DSO. From the way he speaks, the impression that he gave me was that he knows his stuff much better than the NUS lecturer. The lecture this time was more towards the engineering side, rather than the science and vortices and fluid stuff. So it was quite a lot easier to understand. It didn't really teach a lot, but it was a great exposure to what to expect in the field of aerospace engineering.

I mainly remembered two simple things from the lesson. 1) Dihedral wings give a plane stability because rolling to one side will cause one side of the wing to have greater lift. 2) Found out the use of the tail plane. To correct yawing moments of the plane.

Followed by that we went to the field for a flight demonstration. First we looked at an expert flying a huge R/C plane (maybe around 80cm long) with bulky wings. From the looks of it costs around 300 dollars. The thrust it generates is impressive. The range is 2 km. I have had always a liking for vehicles since a child. By imagining little people just beside the vehicle, and making the vehicle move fast, I place myself in the viewpoint of those little people, and thus they look really magnificent to me. I still can't really believe how 'young at heart' or childish or whatever adjective you use to call a person who a few months ago took a big lego commercial jet flying it around the house and making it take off and land over and over again, I am.

Then the guy showed us a big flapping bird which could not fly as fast, but still it can fly faster than I thought. Not very agile. It attracted a bird which flew near, but it soon flew away when it knew it wasn't a bird.

Lastly, he flew a UFO like thing with 4 propellers. By the looks of it, having to control each propeller individually, it is a hard vehicle to control. Then he tried to do a loop the loop with it, and when it reached the top of the loop it thrusted down towards the ground and smashed.

I really hope I can fly a big model airplane someday. Ironically I wouldn't want to fly in a real one for two reasons.

1) I wouldn't be able to witness it flying from the outside. It will be just a screen, like watching TV if I sit inside the airplane. Maybe a wide surround screen, but still a screen.

2) Maybe looking at screens isn't that boring after all, if you see stuff flying towards you without a need of 3D glasses or if you see grounds spinning towards you. But that isn't really the kind of excitement I am looking for.

Roommates

First, I decided that I was probably going to room with Eugene, but wenbo was feeling so emotional over not having a roommate. Furthermore, he wanted one so he could toilet jx and jeremy. Then Raynor came along and asked me if I wanted to room him. I decided that it would be alright, if only Eugene wanted to room with wenbo. Problem is, nobody seemed to want to room with him. So I set up a conference, hoping to deal with this in a just and fair way. Afterall, my conscience got the better of me, and considering that a few decisions would be affecting the lives of a few for a year, I really felt responsible. So we managed to reach a consensus that Raynor, Eugene and I will toilet each other. We had to find a fourth, and upon asking wenbo whether he wanted to be the fourth, on the condition that he couldn't toilet jx and jeremy anymore, he refused. He rather be without a roommate, possibly because randomizing himself will give him a glimmer of hope getting to toilet jx and jeremy. He asked Jk to room him, and at first Jk rejected. Our conference decided that if wenbo did not want to join us, Jk, not wanting to room wenbo, will join in. However, Jk doesn't really sense our hints to him and took wenbo as an insurance lest he really didn't have any roommate. So Eugene, Raynor and I have at least accomplished something, getting wenbo a roommate. But our fourth was still missing, so we asked Tung, but Tung was being stuck up and refused since he didn't want to room with a bunch of 'nerds' which I suppose he should call himself one too considering that he likes physics so much. So during sports day I went to ask Toan. Cmc at the side was not being helpful at all, which I did not appreciate, by pointing out Raynor's flaws. So failed I, in coaxing Toan to room with Raynor. However. Raynor asked Tung again the next day, and he accepted this time, which I no longer cared much for since he have been such a ______. And just when our problems were thought to be settled, I brought up the wrong topic as Jk and I were walking home from DSO, and he kindly revealed his plans to me, and asked if he could replace Tung and ditch Wb. As I questioned him over msn about how he would break it to Wb, he had reservations about it and thus I could not put my confidence in him to settle this in a win-win manner, or perhaps just the best way. Thus Eugene was rather unsupportive of having him as a toiletmate, and I was beginning to have my doubts to. So knowing that although logically it would be correct for Jk to ditch Wb as they had an agreement, it was morally wrong as Jk had knew in advance that the agreement would not be met. So I constantly tried to hint Raynor over MSN that why not we all do some people favours and give unwanted people a chance to have a roommate. Unfortunately, my obvious hints were not understood by him, or even if they were they were ignored, and Raynor called Tung to confirm whether they were rooming. Then Tung said if he was alright with it he would go with someone else, and Raynor just agreed. So Jk came to join raynor and broke it to Wb that he no longer had a roommate. Since I have been part of the conference, I somehow felt responsible, and if I just left Wb like that, my efforts in even, setting up this conference would be in vain. So I had to press on and desperately help Wb get a roommate. Some people already had a roommate, and Toan was the only one who didn't. I didn't have high hopes about it, as he previously mentioned that he wanted to room with people he knew. However I felt that if there were people that he knew who did not have a roommate yet they would have paired long ago, so I accompanied Wb to try to convince him that if he randoms it, he would not only not have the chance to room with someone he knew, and he would instead probably room with someone unbearable to him. So the agreement was closed, and that put a final end to a 5 day conference about roommates.

The End