Friday, April 25, 2008

Distance -> Velocity -> Acceleration ->?

I find it fascinating that you can be charged/fined - not just for driving faster than the speed limit- but if your acceleration is too great. Apparently it is illegal to 'drag' race somebody stopped at a red traffic light- even if your car never actually exceeds the speed limit. Who knew? This is the sort of issue that should have been raised when i was studying calculus about 20 years ago!

But why stop at acceleration?

The rate of change of 'distance' is 'velocity'.
The rate of change of 'velocity' is 'acceleration'.

But what do you call the rate of change of acceleration, or the rate of change of the rate of change of acceleration or.... you get the point.

Believe it or not.. there actually are terms for these but apparently they're not all that widely accepted. Once again to the rescue wikipedia-

The rate of change of 'acceleration' is 'jerk' ...or possibly 'jolt' or 'surge' or 'lurch'
The rate of change of 'jerk' is 'snap'.. or possibly 'jounce'.
The rate of change of 'snap' is 'crackle'
The rate of change of 'crackle' is 'pop'
And since nobody else has claimed it i now official stake my claim to name the next kinematic derivative thus:

The rate of change of 'pop' is 'whoa!'

"I'm sorry officer- was it my acceleration, my jerk or my snap, crackle, pop or whoa!?"


  1. Reminds me of the Italo Calvino story of the car chase. Traffic stalls, both cars unmoving. A chase without movement seems similar to a speeding ticket without speeding.


  2. yeah - love "Time and the Hunter" and "Cosmicomics" .. thin books but difficult and fascinating stories... i always feel creeped out after reading them... like Paul Auster or Haruki Murakami novels.
    i'm a big Calvino fan - IOAWNAT obviously with it's nested self-referrential stories, but i also loved "The Cloven Viscount" (part of a trilogy of novellae), and his massive collection of Italian folktales... what else? "Adam one Afternoon"- short stories- tht was great too esp the one about the ants...'formica?'

    i'm getting nostalgic- gotta find those in one of my book boxes!


Whaddaya think?