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[Music plays]
(Mitch) A little history on this whole idea of spolling,
spinning and rolling.
There was a scientist back in history named Leonhard Euler,
it’s kind of spelt like Leonard Yuler,
but it’s pronounced I think Leonhard Euler,
and I guess he’s done what everyone’s done at some point in time,
is taken a coin and spun it on something kind of smooth and flat.
You can do it on a table, but I’ve got a pretty,
you know, mirror thing happening here, so let’s use that.
And the movement is really unique.
It’s not spinning, it’s not rolling, its spolling,
and one of the things that the mathematicians
get kind of excited about is as the coin gets closer and closer
to the table it starts to spin faster, not slower.
In other words, as it uses up its energy
the frequency of the spolling goes up,
until it hits this singularity where it all of a sudden ends.
I’ll do it one more time, and then I’ll show you something even cooler.
[Music plays]
Now right at the end there is the best bit.
So how can we make it last a little bit longer?
We need a coin that’s kind of more dense I suppose,
or heavier,
and we want to just get this thing going for as long as possible.
We’ve also put some glittery stuff on there, just so that it looks nice.
Let’s check it out.
And it’s going to take a really long while,
because there’s not as much friction acting on this coin,
the corners are really polished,
so we’re going to wait until the very end
and the best bit is right before the thing stops,
at that singularity where the frequency goes up,
and up, and up, and then
[Clap] stops.
Check it out.
[Music plays]
One of the things you might like to wonder about is
what is powering this? Where does the energy come from?
And so if we look in from a side angle,
the overall centre of mass of our coin
is getting lower, and lower, and lower.
So it started off with more gravitational potential energy,
and as gravity pushes that thing down
it’s converting that gravitational potential energy
into kinetic energy, the energy of movement,
and also a bit of sound energy,
and maybe some heat energy in there as well.
[Music plays]
Amazing!