Round Triangles!YouTube↗  IA↗(long shot)
Science & Technology  2.2M views 17.3K likes 289 dislikes   23 Jan 2012
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Contributed subtitles
Korean UCJSC0AKFldKL-3mh4EERTZw
Italian Marco Ebreo
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It makes intuitive sense that objects like circles and spheres are round - but what is
Intuitiv ergibt es Sinn, dass Objekte wie Kreise oder Kugeln rund sind - aber was
it about a sphere that makes it round? If you're talking about how effective a shape is at enclosing a large volume, you mean "sphericity".
macht eine Kugel rund? Wenn du davon sprichst, wie effektiv eine Form darin ist, viel Volumen einzuschließen, dann meinst du "Kugeligkeit". Und eine Kugel ist die Form, die am
And a sphere is the shape that contains the most volume with the least surface area, that is, a sphere is the most "spherical" shape.
meisten Volumen mit dem kleinstmöglichen Oberflächeninhalt einschließt, somit ist eine Kugel die "kugeligste" Form.
But roundness has more to do with rolling than with volume, right?
Aber Rundheit hat mehr mit Rollen zu tun als mit Volumen, richtig? Ein rundes Objekt kann
A round object can roll smoothly - like a wheel or ball bearing. And the main feature that ball bearings need in order to roll smoothly is to be the same
problemlos rollen - wie ein Rad oder Kugellager. Und die Haupteigenschaft, die Kugellager brauchen,
width from bottom to top/one side to the other.
um reibungslos zu rollen, ist, immer dieselbe Breite von einer zur anderen Seite zu besitzen.
It turns out there are plenty of non-circular 'shapes of constant width' that are excellent
Es stellt sich heraus, dass es reichlich nicht-kreisförmige "Formen konstanter Breite" gibt, die ebenfalls exzellente
bearings as well. The Reuleaux rotor, for example, is made up of segments from three circles intersecting
Kugellager abgeben. Das Reuleaux-Dreieck beispielsweise besteht aus Segmenten dreier
at their centers - so every point on a side is the same distance from the opposite corner,
Kreise, die sich in ihren Mittelpunkten überschneiden - also hat jeder Punkt auf einer Seite dieselbe Entfernung
and the rotor rolls around wonderfully. In fact, the Reuleaux rotor can even turn smoothly in a square hole!
zur gegenüberliegenden Ecke, und das Dreieck rollt wunderbar umher. Tatsächlich kann sich das Reuleaux- Dreieck sogar problemlos in einem quadratischen Loch drehen!
But don't try to use a Reuleaux rotor for the wheel on your car - since they're not
Versuche aber nicht, ein Reuleaux-Dreieck als Rad für dein Auto zu benutzen - da sie nicht
a constant distance from the axle, those points will make for a bumpy ride!
gleich weit wie die Seitenpunkte von der Achse entfernt sind, sorgen die Ecken für eine holprige Fahrt! Tatsächlich sind die Ecken
In fact, the points on a Reuleaux rotor are just that - pointy. Doesn't that go against the idea of roundness?
an einem Reuleaux-Dreieck genau das - eckig. Widerspricht das nicht der Idee von Rundheit?
Geology has the answer: stones with sharp or rough edges that are worn away become "rounded."
Geologie hat die Antwort: Steine mit scharfen oder groben Ecken, die abgetragen werden, werden "abgerundet".
So we might say a Reuleaux rotor is round but not rounded.
Also könnten wir sagen, ein Reuleaux-Dreieck ist rund, aber nicht abgerundet. Andererseits sind bestimmte
On the other hand, certain British coins are round AND rounded, though they're still not circles: the 20 and 50-p coins are shapes of constant width, which means they look un-circularly
britische Münzen rund UND abgerundet, obwohl sie immer noch keine Kreise sind: die 20- und 50-Pence- Münzen sind Siebenecke konstanter Breite, was bedeutet, sie sehen unkreisförmig cool aus, ohne
cool but don't get stuck in coin machines!
in Münzmaschinen stecken zu bleiben!
And isn't if funny that "rouleau" means "roll" in French and Franz Reuleaux invented a rolling
Und ist es nicht lustig, dass "rouleau" das französische Wort für "rollen" ist und Franz Reuleaux ein rollendes
rotor?
Dreieck erfunden hat? [Und was ist mit Rowling?]
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