Re: Work/Energy theorem?

[Leigh Palmer <palmer@sfu.ca>]

> At 07:57 AM 4/5/97 EST, David Bowman wrote:
> [Shapiro]
> > > >       Yeah..... Sure you can tell the difference.  If "what you feel" is
> > > > too crude a measure for you, use an accelerometer.  My claim is that the
> > > > guy on the ground will see a reading of zero on his accelerometer, the guy
> > > > on the train will see his accelerometer read different from zero as the
> > > > train stops.
> [Leigh]
> > > John, Albert, and I will all be surprised by that result. I'm distinctly
> > > uncomfortable whenever my accelerometer reads zero!
> [DB]
> > I too would be surprised by that result....
> > David Bowman
> > dbowman@gtc.georgetown.ky.us
> ...But not me. I deal with reality.
> I realise that the accelerometers I deal with are generally
> single axis instruments.
> So that they read 1 g upright, -1 g inverted, and 0 g
> at 90 degrees of rotation.

In Canada we teach our students that acceleration is a vector quantity.
Inside my middle ears I have two accelerometers that, when they are
working, reinforce that impression.

It appears to me that all of us understand what the correct answer to
the question at hand is. Why is anyone quibbling? Does anyone honestly
disbelieve the (local) principle of equivalence?

Leigh