What is Inertia

[Farrell]

Sarah, Mark and Jim are headed in the right direction.

An object's inertia is directly related to its mass and velocity. The more
mass it has and the faster it is traveling, the more inertia it has. A
bullet, travelling at some very high velocity, could have a similar amount
of inertia as a very slowly moving locomotive.

Basically, a good way to think of inertia is, the harder it is to stop
something, the more inertia it has.

Terry Farrell

----- Original Message ----- 
From: "Richard Brekne" <Richard.Brekne@grieg.uib.no>
To: "College and University Technicians" <caut@ptg.org>; "Newtonburg"
<pianotech@ptg.org>
Sent: Wednesday, December 24, 2003 6:22 AM
Subject: Re: What is Inertia


>
>
> "Don A. Gilmore" wrote:
> >
> > There are no units of "inertia"; one  object cannot have more "inertia"
than another.  It can have more kinetic
> > energy, or momentum, or mass, or velocity, or indeed "moment" of inertia
> > than another object since those are measurable, quantifiable properties.
>
>
> I understand exactly what you are saying, as I understand exactly what
> the others are saying. But I have to point out (without taking a
> position on the matter myself) that there are three declared definitions
> for inertia on pianotech by various folks with some degree of physicis
> knowledge. Let me list them.
>
>
> 1. Don Gilmore... inertia is a concept, not a quantity, has nothing to
> do with size, mass, velocity or anything else. Is simply the fact that
> objects with mass tend to resist any change in velocity. No object
> regardless of mass has any more inertia then any other mass.
>
> 2. Sarah and Mark.... inertia is very much like Don describes, yet
> inertia is mass related... a larger mass will definatly have more
> inertia then a smaller mass.
>
> 3. Jim Ellis.  inertia is clearly mass related its very hard to read his
> definition without concluding he means that inertia is related to
> acceleration and /or velocity... That  relation to acceleration seems a
> bit unclear... but as I read through his posts I get that he first
> said... Inertia = mass x velocity-squared, then after some debate
> changed this to Inertia = mass x acceleration-squared. His last post
> seemed to draw this up a bit differently
>
> "Inertia is a minifestation, a property, an effect, of acceleration and
> deceleration.  It's proportional to the square of the change in speed,
> or velocity."
>
> What I'd like to see at this point is that since Don, Sarah, Mark, and
> Jim all are people we all rely on for physics insights, and because they
> all present clearly different definitions of this concept,,, that these
> four all bang this one through until they arrive at a common definiton
> for us.
>
>
> grin.... NOW I will state my own position... tentatively...ok ?? :)
> Seems to me that Don is correct... except I have a hard time
> understanding or accepting that "one  object cannot have more "inertia"
> than another". If this is true then either inertia is a constant, or
> inertia is just plain undefined... as in divideing by zero more or less.
> So I lean towards Sarah and Mark. But I want to see you 4 hashing this
> out so we can past the problem.... as clearly any discussion about
> action mechanics on this list is going to be rather meaningless unless
> we can agree on what terms like inertia mean.
>
> Cheers
> RicB
> _______________________________________________
> pianotech list info: https://www.moypiano.com/resources/#archives
>