Euler Column Buckling

When you're biking for many hours each day, one may wonder what gets thought about.  Today my brain rolled over column buckling.  That's where you take a long slender column and push on the ends until the thing snaps.  What got me thinking about this was a little incident with the tailpipe on our companion vehicle Honda "Excrement".  I'll spare you readers the details, but let's just say that the exhaust system is a long slender column and that the ends got pushed on until the column buckled.  So for all those who are now bored beyond recognition, here's the end of Montana and the beginning of North Dakota and also Paul C. cycling alongside Sentinel Point, just inside North Dakota.

 



So the interesting thing about column buckling and how it applies to life in general is what happens as the column is loaded.  When you push on one end of a column (axially) with the other end fixed, nothing happens.  You push harder and still nothing happens.  Then, if you push hard enough, the middle bows out and the thing fails.  The interesting thing about this is that it never moves in the direction that you are pushing.  The middle bows out orthogonally (at a right angle) to the way it's getting pushed on.  Many things in life are like this - You may ask someone to do something for you, but if the request is made in an arrogant manner, the one you are asking may not do what you wish, or could possibly do something opposite to what is desired.
OK, another commercial break...Below is another abandoned homestead, along with a prairie dog on top of its mound.

 

So what got me thinking about all this was when we were looking at the exhaust system, we saw that it had been pushed sideways in the middle of the car.  But it didn't make sense that anything could have pushed it in between the wheels at right angles to the direction that the car traveled in.  Only when we considered column buckling did what we observed make sense.  So what's the lesson here?  One is that pushing in the direction that you want things to move in may not always be the best strategy.  The other is that movement in a certain direction does not always imply that it was pushed in that direction.