> I see... So the resonant modes of something are all possible standing 
> waves that can be created in that space?

Yes I guess so.

> "2nd moment of area"? ._.

Determines the geometric stiffness of a cross-section.  Basically the more 
"material" further away from the axis of bending the stiffer it will be.  So 
if you have an area budget of 10cm^2, better to put it all as far as 
possible away from the centre (ie a circle), or if it only needs to bend in 
one direction, then two parallel plates (usually connected though, so that 
will be an I-beam then).

> Apparently the governer just fell off, and the engine is now running at 
> full tilt in neutral with the fuel injection system at non-default 
> settings.

I had a similar thing happen to my radio controlled car, the throttle fell 
off, literally the bit that regulates the air-flow into the engine fell out 
of the air intake.  Of course then the car is going full throttle in a 
street full of parked cars and all I can control is the steering!  Finally I 
think it got wedged underneath a real car and not too much damage.  I found 
the throttle too and put it back in, with some loctite this time!

> Cut to a scene 20 minutes later, and they've taken the head block off the 
> engine, and the team captin is holding up bits of pistol rods, and other 
> items which look like they really ought to be *attached* to something, but 
> clearly aren't...

Try running a lawn mower with no oil, part way through cutting the grass it 
stopped, not like the running out fuel stopped, but instant stop from 200rpm 
or whatever to silence.  Took the head off, a big bit of wood and a big 
hammer freed up the piston from the side of the cylinder, then a good dose 
of oil and it was working again!

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