Kind: captions
Language: en
All right, we're ready to do this
experiment. I have the two 1.5 kg masses
separated by a copper wire, and my
housemate and assistant Colette has the
two 1.5 kg weights separated by some
fishing line. They're both the same
thickness, so we're going to put them on
simultaneously and see how they go in
cutting through the ice.
How's yours?
[music]
All right, we're roughly halfway through
the experiment, but I ran into trouble.
the uh copper wire actually pulled out
of these weights and so they fell to the
ground. Um, at this point it looks like
the copper was doing slightly better
than the fishing wire. Um, but I've had
to rig up a new copper and so uh I'm
going to try it in a different spot and
let this new copper compete. I also um
scraped off the insulation. There was
some enamel coating on the copper wire.
So I've scraped that off. So it should
just be straight copper wire now. So
let's see how it performs.
[music]
All right, it's half past 1, but it
looks like the experiment is over and we
have a winner. a copper wire pulled
clean through the block of ice while the
fishing line is still stuck in there.
So, why was that? Why is the copper
better able to pass through this ice
block than the fishing line? Well, I
think the answer may have something to
do with thermal conductivity. The copper
is a better conductor of heat than the
fishing line. That's important because
as the wire passes through, the ice
refereezes once the wire has passed and
that releases heat. If that heat is
transferred quickly, it passes to the
ice below, melting it and allowing the
wire to move further and faster. Now,
regulation is not just some abstract,
useless scientific concept. Every time
you make a snowball, you compress those
ice crystals of the snow. And when you
compress it,
it melts a bit, turning into water.
But as you release the pressure, it
refreezes.
So, what we've made is a snowball. Think
about that next time you're having a
snow fight.