Alla inlägg den 18 juni 2008

Av dennis hägglund - 18 juni 2008 06:49

If you wish to proceed using your own slide-show as per below, rather than waiting until I have put one together, the second experiment is simple enough to describe. Perhaps your own logic will make some adjustments/improvements.

First we need to show centrifugal force. Simple. A string and a weight. This is to show that the Earth and other planets and plastic celestial bodies that are spinning are flattened, so that they are fat around the equator, or so that the distance through the centre from equator to equator is much longer than the distance from pole to pole.

Second we need to show how things can be twisted by this force. We know that a swing with one rope longer than the other will not ride evenly. What we need is two strings looped at one end. A stick or pencil to serve as the top of the swing, and something to serve as the seat. We make this little doll size swing do loop-the-loops, over the top several times, and with one string longer than the other the strings will twist predictably. And if we turn the swing around so that the other string is longer it twists the opposite way.

Third we want to show that a weight dangling perpendicularly from a pole of a globe that is flattened sees a smaller outline or silhouette of the planet or body if the string is longer. This can probably be done with just a diagram, although a more interesting demonstration might be of value.

Fourth we want to have it understood by the students that the first thing we recognise chronologically about the evolvement of the universe we live in is a dispersal of hydrogen and perhaps helium atoms, the simplest atoms. These atoms filled the space we now occupy and there was nothing else on that scale or larger around.

That these atoms also had to grow from something is plain enough, but the fractal microcosm is another study, and not really required for this experiment, except to say that gravity is not limited to any size particle, the iterations of the atom being exponentially separated, so that the search for the graviton would seem rather an ambitious place to start. Needless to say, these primary atoms did find each other attracting.

Fifth we show the students that the water will always select to go down a drain twisting in the same direction.

We are not teaching physics to these children. This is about spontaneous discovery. We want to minimize the role of teacher. We want to eliminate the pride of knowing. Make a vacuum of teaching and see if there is some hope that this will bring out the eagerness to discover rather than the irrational conditioned reflex to know. We also do not approve of those who discover; we eliminate the reward gimmick. Discovery is its own reward. Discovery, not a reward, is what we want to share, or it isn't discovery. And we don't want the next person to know it, but to discover it.

Next, of course, we present the slide-show, letting the students control the next and previous buttons if possible.

Av dennis hägglund - 18 juni 2008 03:07

The second Discovery Moment experiment involves some pictures, although not in the same way. I will be putting a slide show on a site, and you can just collect it. But some people are shy about clicking on a .zip or and .exe file, and I have made the pictures 1024x768, to fit most tellys and monitors, wjile there are much larger files on the web. In either case, I suggest you collect images from the web yourself using the following search words: hurricans, typhoons, tornados, dust devils, whirlpools, galaxies and the planets with the rings. I have personally used a downloader called Grab JPG, which is free and flawless for 15 days. If you have a budget processor like mine you can't let it get too far ahead of itself, say past 1000 images in one search. I also recommend XNView, as an image managing tool, also free, but no time limit. The .exe files, self-executing slide shows, I make come from there. If you ae having trouble with your Google, I suggest Alta Vista and Dogpile, which I have put in links to.

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