Kind: captions
Language: en
So, I'm down in West Vancouver, British
Columbia, which is where I grew up. And
uh at the local beach, there is this 2
and 1/2 ton granite sphere that was made
to have a tolerance of 200ths of a
millimeter. This is an amazing uh
granite sphere, and it's floated on a
thin layer of water. And it just
presents an amazing opportunity to study
inertia. And that's why I'm down here to
have a chat with uh with some of the
people going by about why the globe
spins and in fact why the earth spins.
Why does the earth spin? Why does it
turn like that? Um I think it's the
gravity for it to keep us down on the
ground. Is that right?
Gravitational pull.
How does that cause the earth to spin?
Again, my basic science fails. It's
fails. Gravity. I he he guesses, you
know, looking.
Gravity. Oh, yeah. Gravity.
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It's not stopping. Would you agree with
me?
Yeah.
So, why is that?
Some sort of force. That's
You think there's a force down there
pushing it?
Yeah.
I'm going to go cuz the up thrust from
the water is probably angled in such a
way that it's because it's a spherical
shape, it's probably pushing on it at an
angle, so it spins constantly.
Yes. What is the centrifugal force that
keeps it keeps it going? What is that
force? Where does that force come from?
Is there a force that keeps it going? Is
there a force pushing it around
within within uh within the earth's
core? Is there not something that drives
and dictates said centrifugal force?
Guess it's the law of inertia, isn't it?
What's the law of inertia?
Every action pos equal and opposite
reaction.
The force of inertia maintains this um
but inertia which is a great idea is not
a force.
How would you define?
It's just the tendency of all objects
with mass to maintain their state of
motion.
Okay.
So if they're stationary they want to
stay stationary
if we anthropomorphize them.
Yes. And if they're moving said
anthropomorphized objects want to want
to keep moving
keep moving. Basically whatever motion
they have they like to continue in that
state of motion. The earth does that
without any forces. This does that
without any forces.
Yes.
Yeah.
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