The wonders of the isochronous curve

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I can’t wait until the Ratel kit is old enough to sit down and wade through hours of awesome videos like this with me.

Right now it has to be garbage trucks, with the occasional allowance for Daniel Tiger or Shaun the Sheep.


Shaun the Sheep got his name as a throw-away line in “A Close Shave” - he’d gone through the Knit-o-Matic and come out completely bald, so Wallace named him “Shaun” (Wallace pronounces “shorn” and “Shaun” identically). I’ve only seen one or two partial episodes of the spin-off series, but as far as I’m aware* they’ve never referred to the origin of his name again. I love that level of confidence in a joke.

*If I’m wrong and they did rehash the joke… I’m not sure I want to know about it.


I didn’t really follow the science part of this, but I did see an oblique and non-condemnatory reference to tobacco, so I think I’ll take up smoking.

children, I guess


Beat me to it. I also recommend the video Michael mentioned, below.


Thank you. I will give this a watch tonight when I get home.

Everyone in the US has to have it explained to them. “No, no, but if you say the two words with an English accent…”

I was a little disappointed that there was no reference to W&G even in the movie, but they also seem to have cut them out when they make references to Shaun’s youth in various episodes (making look like he’s always lived on the farm). Shame.

The series is plenty of fun for adults (and uproariously funny to a 3-year-old). For adults, though, I’d recommend Golly’s other Nick Park TV adaptation: Creature Comforts. His series is equally if not more amazing than the original short.


I have a feeling this would apply to a precision clock pendulum. The earliest ones had these metal plates shaped like a gable to force the pendulum to change its path, and it always confused me as a horologist.

Now seeing this concept, I finally understand how it worked, and why Christian Huygens was trying to do that on his clocks- it was to make the pendulum arc through a shape like this curve.

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Wow, I had entirely forgotten about this show, but used to watch it religiously as a kid.


I remember from university the first day of my differential equations class where the professor asked us what curve would bring a ball down to ground level the fastest.

A little back and forth and some math and we got to the isochronous curve.


Aw! I came here to drop Three Blue One Brown’s:

EDIT: Ninja’ed by @spetrovits


That answers my next question:

The tautochrone problem was studied by Huygens more closely when it was realized that a pendulum, which follows a circular path, was not isochronous and thus his pendulum clock would keep different time depending on how far the pendulum swung. After determining the correct path, Christiaan Huygens attempted to create pendulum clocks that used a string to suspend the bob and curb cheeks near the top of the string to change the path to the tautochrone curve. These attempts proved unhelpful for a number of reasons. First, the bending of the string causes friction, changing the timing. Second, there were much more significant sources of timing errors that overwhelmed any theoretical improvements that traveling on the tautochrone curve helps. Finally, the “circular error” of a pendulum decreases as length of the swing decreases, so better clock escapements could greatly reduce this source of inaccuracy.



Same here. This was one of my favourite things on TV during the 70’s and Rob and Deane were great ambassadors for science. Thanks @frauenfelder for the link to their YouTube channel.


Creature Comforts changed my life.


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