During our orientation week all the teaching assistants (TAs) received a brief training of how to teach. Part of this workshop was the presentation of a short, simple mechanics problem. My problem was about a super-fast car which had a certain speed and was supposed to stop in a very small distance. Then, calculate the deceleration.

Paper in the US is broader and shorer; the holes are also pinched differently. To fit both formats into one folder, I developed the grand unified pinching pattern (GUPP) as above.

I presented my ideas on the board (everybody had seven minutes) and afterwards I gave a brief discussion if the solution was "sensible", i.e., in the expected order of magnitude. (Sometimes it happens, that you get a negative mass or the like - then you know at least, that something in your calculation must be wrong.)

So I talked freely of how many kilogramms would weigh so and so many Newton which would result in the same force as it was necessary to stop the car. At the feedback session there were no actual complaints despite the comment, that I could imperial units (pounds, miles, inches...) for the illustration ;-)

But I have got absolutely no intuition for those units! I don't see a building and think, oooh, that's about 30 feet! Nor do I have any idea, how fast 25 miles/hour are. It's probably worst concerning the weather: Now it's 80°F and I'd think, that's hot, because Celsianer live on a different scale.

When I met other international students, they agreed that Celsius is comfortable for intuition and seen the temperature relative to the melting and boiling point of water. But the US-American guys argue that they don't need decimal places for Fahrenheit, which makes it easier (aha ;-) ). Anyway, in Santa Barbara one does not really have to care about the temperature because it's nearly the same all over the year ;-) And even if, I'd plead for Kelvin!

Another problem is the paper format. The average paper you write on is a bit broader and shorter than its European brother; there are also three holes per paper and not four. So you need an US-American hole pincher. And have your old notes pinched twice (as above) to get them into an American folder...