so I'm down in West Vancouver British
Columbia which is where I grew up and at
the local beach there is this two and a
half ton granite sphere that was made to
have a tolerance of two hundredths of a
millimeter this is amazing
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 the 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 I think it's a gravity for it
to keep us down on the ground alright
gravitational pull well how does that
cause the earth to spin again my basic
science fails it's failed good gravity
I'm he guesses you know looking gravity
oh yeah gravity we realize 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 gonna 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 for
soon where does that force come from
isn't our force that keeps you going is
there a force working around within
within within the scores and not
something that drives and dictates said
centrifugal force
it's the law of inertia in it what's the
law of inertia every action causes equal
and opposite reaction if the force of
inertia maintains this but inertia which
is 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
and if we anthropomorphizing yes if
they're moving set down to polarized
objects once it want to keep moving
basically whatever motion they have they
like to continue in that state of much
yes the earth does that without any
forces this does that without any force
yes yeah
you