Not wanting to crash and die will tend to motivate. :)
Yup, that'll do it. Usually.
It's too bad that typical students don't more fully appreciate
the connection between classroom physics and real life.
But there are steps that can be taken. When a student writes
down an answer with no units attached, I tell 'em the next
time they do that, the penalty is 328 million dollars. I
thought of using some Avery label stock to make Mars Climate
Orbiter mission logo stickers to apply to the offending papers,
but I wasn't ornery enough to actually do it.... http://www.av8n.com/physics/math-hints.htm#main-dim http://mars.jpl.nasa.gov/msp98/gif/m98patch.gif
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Also, if you want to pursue the dimensional analysis angle,
here's a fun thing, a calculator that keeps track of units: http://www.calchemy.com/uclive.htm
Some guy named Walter E. Brown at Fermilab put together a c++
class library to do something similar, but it hasn't been touched
since 1999 AFAICT, and doesn't compile under ISO standard c++. I
looked at it and deemed it to be overly complicated and underly
documented, so I wasn't eager to jump in and fix it.
==> If anybody knows of a similar c++ thing, open source, please
let me know.