Hey it's me Destin
Welcome back to SmarterEveryDay
So you've probably observed that cats
almost always land on their feet
Today's question is why.
Like most simple questions there's a very complex answer
For instance let me reword this question
How does a cat go from feet up
To feet down
In a falling reference frame without violating the conservation of angular momentum
Now I've studied free falling bodies, my own in fact
in several different environments and once i get my angular rotation started
in one direction, I can't stop it.
Today, we're going to use a high speed camera- we're not going to use Alley
because this is my daughter's cat, i don't want to hurt it-
we're going to use a stunt cat
let me introduce you to Gi-Gi
the stunt cat
(music)
I'll just flip the uh, the video vertical
and then motion track the cat
it's just going to take a lot more effort in post
We're going to try to do it in a way that doesn't make anybody mad
That's pretty hard to do.
You gotta drop the cat
Ready Gi-Gi?
Good kitty
Checking out the high speed data there Gi-Gi?
Ok the first thing a cat does when it's falling is try to figure out
which way is up.
It does this either with the gyro in the ear
or with its eyes
Ready to talk cat physics?
Alright. So check out this footage i captured with the Phantom Miro
While Gi-Gi goes to get a drink of water.
So here's what's interesting about this to me.
You'll notice that at the beginning of the drop the cat
is not rotating
halfway through the drop the cat is rotating
and at the very end Gi-Gi somehow stopped rotating
Newton's law says an object at rest will stay at rest
unless acted on by an external force
I see no external forces on this cat
So what's happening here?
It's not making sense to me
O.K. so in order to really get the right data
we're going to have to drop her 90 degrees out of phase.
Atta girl
This time watch her tail
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