Why golden trash bins do not help (modern equipment in schools)

Hi,
(few days back) I am sitting in a classroom, slightly bored by the teacher saying what I heard the day back. After few minutes I am being offered to do experiments alone. I agree with the hope that it is going to be more fulfilling. Instead of getting full access to the laboratory[1] I sadly accept white box, aka trash bin.

https://www.fdgate.com/photo-2/high-school-physical-optical-experiments-box-experiment-box-lens-optical-instrument-physics-experiment-equitment-m-0915.jpg

This is kind of similar, the fact that it is chinese[2] kind of fits the situation since my german is not so good yet.


Such a box contains “scientific” equipment for the study of electro-magnetism. This consists of few cabels, power source, resistors, capacitors, all properly laid on green boards. Function generator, some frequency and amplitude thing, two coils, magnet and some stuff to hold it together. This is probably almost perfect list of things that costs the school hunderds of dollars. I took it with the manual that contained roughly 15 experiments and decided to do one of them. I put components together as it said, found out the thing it said I am supposed to find out, it gave me the formulas to calculate it.. that is all.

So now the rant against these boxes (thrash bins as my host-brother pointed out).
The problem is that such a box with set up equipment and set up experiments does not enhance any creativity in students. Especially building circuits could be one of the cool things where you try what happens when you connect this and that. That is probably the biggest problem, you can just follow some manual and not understand what is going on. Also these components are totally dependant on each other and you can use only this box alone, there is no room for expansion or only limited. Not speaking about the cost, there is another trash bin like this for 800 euro. It had wagon, line on which the wagon could drive, two movement sensors and some things to hold it together and so on. We used it during physics class to demonstrate Newton’s 2nd law (F=ma). It took so much time to set it up, to measure it all to 3 decimal places. Actually it took 90 minutes and we did not get even to the formulation of the law. People were bored and I bet that if you asked half of them what was this whole about they would not have a clue.

This is modern equipment.. and it is useless. If they bought separate components boards to built circuits on, they even have those in the school but they are not used anymore. These days teachers probably think that they can not get better with chalk and a board.

Dragallur

[1] I do not think it would be a good idea to let me there alone though I go there anyway every monday with my host-brother.

[2] I do not know if it is chinese.

Tug of war: How to kill yourself!

Hi,
today we had some program with whole school. It involved costumes on specific themes and also contests. One of the contests was tug of war.


Our school is fairly small compared to ones in USA, we have only 360 people. Some were not there of course so we can speak about three teams each with 100 people. There were even very small kids (10 years old) so the force was not so great, but then again.. 100 people on each side we could excert force of about 500 kilograms I would guess. At first I though the rope would snap immediately, but it was climbing rope and after I searched at home, the rope would probably survive force ten time great.. uff, we are lucky that they chose such rope!

So it did not snap.. in the first match we lost but we did not hear that it ended and thought the second team was just growing weaker so we pushed harder. At the point they were not holding it tightly at the end (it was long rope). The rope accelerated a lot and it burned their hands.. the same thing happened to us for the second time. I have little white one finger, but it is ok. When I came home I decided to search something about tug of war..


 

When two large teams pull the rope, it stores tremendous amount of energy. When one team just let the rope hang not very tightly the other team will burn their skin off their hands. And they are actually very lucky!

Why? Well the rope can snap, and this does very bad things because this energy is released at the same time.

Let me give you some examples how dangerous tug of war may be with lot of people:

In 1997 in Taipei there was some celebration of 52nd anniversary. Of course they had to take over 1,600 people into that game. So many people excerted force of 80,000 kilograms while the 5 centimeter nylon rope was able to withstand only 26,000 kilograms! Guess what! The rope snapped!

When snapped, the energy was released in what is called: sheer rebounding force. It tore off whole arm of two closest man. Seriously.

In 1995, first time one man wrapped the rope around his hand, it tore his hand off again. In the same year, 650 people participated in match with nylon rope. Again but worse this time, as the rope whipped back, it instantly killed 9 year old kid..


Just for you to know when someone decides to create huge tug of war match, stop him!

Dragallur

Check out these pages for more info: 1) 2) 3)

 

 

Creationism vs Science: Should we teach it in schools?

Hi,
yesterday I wrote kind of prologue to those series about science and creationism. I talked about looking on the other side and not just staying on your opinion. Now as I promised this post will be about the learning of creationism in schools. I also noticed that you guys actually commented on my post which I am very happy about, so thanks again!


It has already been few months but after having the discussion about creationism I remembered it again. In our biology class in autumn we were starting to learn about the life on Earth.

My teacher said that there is an evolution and there are also other version about how it happened, creationism for example. But she said that she wont be learning us about creationism and will left us with the knowledge about evolution (we learned just few basic stuff anyway).


Now when I think about it, this sounds to me kind of unfortunate[1]. Why? Because those people who wont happen to think about it in soon future will at some point get the information, but from what source? Will it be objective (not saying that teachers are always objective, but they should be)? Plus, creationism is such an important thing from the matter that so many people believe in it and in past 99% of people thought it to be true, so how should the class look like?

I think that the teacher should explain on what creationism stands. Seven day creation, how Earth is only 6,000 years old and the Great flood. Then she/he should let the students think about this. I think that on this you can so well show how argumentation work, for example student just can not say that he thinks that seven day creation is stupid. This could learn them a bit of critical thinking and argumentation, though there is one problem.

What if in the class were some people who actually belived in creation? I mean they were surely learned by their parents about creation. Of course it would be in their greatest “benefit” to tell them about evolution and why some things are simply made up about creation, but if I think about how groups of people think in classes maybe it would be kind of like showing all the other students who were taught about the “scientific way” that those two or three students are stupid. This seems to me how it could end and there would be no benefit in it at all, I can imagine how those kids could be kind of stressed if they should trust in evolution or creationism.

What to do with it? Well you could probably pretty much eliminate the problem if you would teach it in higher classes for older students when they are more self-confident and so on, but I do not have the right experience with teaching to really tell how it would end up, still I think that it is important to learn about creationism because then later when those people who did not ever bumped into such thing could easily “convert” to creationism, and as Mike M. quoted Bill Nye, it is not beneficial for the perspective of humanity to have people believing creationism because “nature and the universe can be dismissed by a few sentences translated into English from some ancient text, you’re not going to continue to innovate” (Thanks Mike.) And trust me, if you do not know anything about the facts that creationists are using it is extremely persuasive. And yes, large percentage of population, even adults just do not know about those things as far as I know [2]. This is because it was seemingly never important to them, this leads to distrust to science and people not supporting it. Take NASA for example, just because of landing on Moon, one of the most amazing achievments of humanity, it is by part of USA population hated, just because there appeared a group of people, who were able to create arguments, which are easy to understand, but they are not true at all. Those are for example flag flapping in the breeze or blast crater under module and so on, this is practicly the same case.

Thanks for reading, next time on those series I will probably “touch” God a little.

Dragallur

[1]Of course there is limited time in class so learning about creationism would take probably two classes, maybe three depending on the teacher.

[2]I must admit here that I do not have representative sample to tell such a thing but when I see my fellow classmates I am sure that they do not care about science at all. Plus I just found out about some people who think that Earth is flat, so thats it 😀 .

 

 

Chemical bonds

Hi,
this post is just a systematic list and explanation of chemical bonds because I needed to learn them for chemistry class and at the same time, why not make a post from it?


 

Chemical bonds are bonds between two atoms. There are various ways in which they can “connect”, and that is what this post is about:

Covalent bond

Covalent bond is bond between two atoms which causes sharing of electron pairs. The difference between electronegativity is less than 1.67. If it would be bigger than the bond would be called ionic bond. Covalent bond is always going to be between two same atoms, for example H-H or   C-C and so on.

EDIT (18.2.2016): Also if the difference is less than 0.4 the bond is nonpolar while if it is between 0.4 and 1.67 it is polar bond. This is important when you want to dissolve some stuff because only polar things with polar dissolve and nonpolar and nonpolar while not polar and nonpolar. For example water has polar covalent bond because the difference is roughly 1.2 or so.

Ionic bond

Ionic bond is extreme case of covalent bond since the difference between electronegativity of two atoms is greater than 1.67. This means that one atom is going to attract the other electron so much that the first atom wont even hold it anymore. Examples of such cases are: Na+ and Cl or Li+ and F .. this “plus” means that the electron was moved a lot towards the other atom while “minus” means that the atom has a lot greater electronegativity and is able to catch this electron causing the atom to be negatively charged.

Above you can see how atom of fluorine takes one electron from lithium under his control (red arrow). Such molecules are easily dissolved in water and they are called non-polar molecules.

Dipolar bond

Dipolar bond is very similar to covalent bond and it can create when one of the atoms do not have any free electrons while the other one has two in one orbital. One of them then may move to the first atom and create bond with the other electron which is alone now.

Because bond can always create from electrons of opposite spin, with dipolar bond you can be sure that it will create because both the electrons came from one orbital so they have to have opposite spin.

An example of such a bond is NH4. Nitrogen has three orbitals ready to be connected with hydrogen which happens. Then the last hydrogen is actually H+ so he does not have any electron but nitrogen can share both his electrons from 2s2 orbital as you can see on the next picture. Here nitrogen is called “donor” and hydrogen “acceptor“.

Metallic bond

Metallic bond is very often seen on metals and it is the reason for their thermal and electric conductivity. As you can see below atoms are all positively charged, which means they are cations while their electrons keep flying around making what is called “electron gas” (as you can see on the next picture), that is why the current so easily “flows” through metals.

Dragallur