Re: Today's jaw dropper

[John Mallinckrodt <ajmallinckro@CSUPomona.Edu>]

On Mon, 6 Oct 1997, Daniel L. MacIsaac wrote:

> > My *guess* is, pretty close to the speed of light and it is borne out by
> > my calculation of .999988 c.
> Sure, John -- looks good.  However, relativity is Chapter 25 in Wilson;
> and this problem is in Ch 15.  

I figured as much, but I thought I'd tweak you anyway.  Several folks have
tweaked me as well for my "bullet around the moon" problem too, but I
think there is this difference: Your problem (despite the questionable
nature of the assumptions alluded to Leigh) at least *can* be answered
with the given information.

> ... Is it even appropriate to describe this
> electron as having 10^8 eV of Kinetic Energy?  I think I would phrase an
> energy description of such an e- quite differently.

I see no problem with defining KE as the excess energy due to motion.  as
is routinely done.  Of course, for very high energy particles, KE and E
are virtually indistinguishable.

John
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