Forces and other tedious stuff

By Marcus Wilson 02/02/2011

I am a bit concerned over the attitude of the kiwi guy interviewed on CloseUp tonight, as he prepares to defend his home in Cairns against Yasi in a house 4 metres above sea-level when a 5 metre storm surge is predicted. You do the maths. Let’s pray that destruction is just limited to things that can be rebuilt.

On more physicsy matters, this coming semester I’m teaching a paper on Dynamics, for the first time, to cover for a  Mechanical Engineering lecturer who is unable to teach it this year.  It’s a pretty turgid subject, really – all about working out how things move when various forces are applied. It brings in concepts such as torque and angular momentum, centre of mass, centre of rotation, internal constraint forces and other unexciting stuff.

Now, my colleague has kindly furnished me with the text book he uses. Ideally this should help, but after going through it I’m of the opinion that all it does is emphasize how tedious the subject is. Next week I shall be digging in our (refurbished and very flash-looking) library for Feynman’s lectures on physics and having a look at how he deals with it. If Feynman couldn’t make it at least a little interesting, there really is no hope.

However, the major gripe I have with the textbook is that it reduces the subject to a series of unrealistic, oversimplistic, stereotypical problems. These problems suggest that it is all about picking the right formulae and doing maths. Real physics seems conspicuous by its absence. Where are the real engineering problems, like the Karapiro grandstand problem? (I really hope that the engineers who designed the grandstand did know a bit about forces).  I refuse to teach that physics (or, indeed, mechanical engineering)  is about sticking numbers into formulae, which, probably means I’m going to have to ditch that textbook and get something else in place (by the end of this month).

Anyway, I’ll keep you posted how this goes as the semester unfolds. And whether I want to teach the paper again once semester is over.



0 Responses to “Forces and other tedious stuff”

  • Real-life problems… cars on a wet road? Comet Shumaker-Levy crashing into Jiupiter? being in just the right place & time to pop a photon torpedo (or whatever it was) down that oh-so-convenient tunnel-to-the-core in the Death Star?