Inertia and Physics- was "Key Inertia"

[Sarah Fox]

Hi Ric,

> So, if both Don and Jim, come right out and agree with Sarahs following
> statement and both are in agreement that inertia has nothing to do with
> velocity or acceleration... then we are are all on the same page.
>
> "The more massive the object, the greater the inertia, the greater the
> force
> needed to set it into motion -- or halt its motion -- or change its
> motion."

Oh, no!  That email (about large bodies at rest on Christmas Day) wasn't
meant to be taken seriously.  Technically, the same force can be used to set
any object into motion -- or halt its motion -- or change its motion -- even
by the same amount.  The ion propulsion engines proposed for deep space
travel are a perfect illustration:  Very, very tiny force needed to
accelerate a large space craft to velocities approaching the speed of light.
There are issues of force over time and distance here!  In short, in the
crafting of a Christmas joke, I misspoke.  I probably should have said:

"The more massive the object, the greater the inertia, the greater the
energy needed to change its velocity by a given amount."

That would work!  ;-)

I hope I didn't contribute to any confusion here...

Peace,
Sarah