Re: [Phys-l] Fun/cool unit conversion example?

[Stefan Jeglinski <jeglin@4pi.com>]

> I thought I would ask here to see if anyone had a neat unit conversion
> example that left you with a sense of "huh, I didn't know that" or "that was
> cool!" or something similar.

Perhaps too trivial for your purposes, but the conversion from mph to 
feet/sec is 3/2, to within about 3%. Simple to derive, good as a 
simple exercise of doing math in their head (how to take 
one-and-a-half, or inversely 2/3, of something**). Gets them doing 
the conversion (and something to ponder) while driving (especially) 
or biking or hiking or running, for example.


Stefan Jeglinski


** which also leads to pondering/learning why, when they multiply by 
1/2 and add, the inverse is not to multiply by 1/2 and subtract.