The Geometry of a Cow

There’s an old physics joke about the dairy (Motto: “Smell Our Dairy Air!”) that hires cosultant after consultant to help optimize their milk production but to no avail. Each and every time, the end result is that nothing has improved. Finally they hire a physicist, who comes in and takes all sorts of data, and then retires to his office, madly doing calculations. After waiting a while, the dairy contacts him, inquiring about his recommendations. He come in to do a presentation, with all sorts of papers and slides for the overhead (or powerpoint on his laptop if you want to update the joke). He puts up the first slide, and starts in with, “First, we assume a spherical cow…”

It’s funny if you know physics, or more specifically, physicists, who tend to idealize all sorts of things in their models. (frictionless surfaces, elephants whose mass a may be ignored, etc.)

Anyway, hop in the wayback machine to a few years ago, when several of us were having a discussion about problems on our comprehensive exams in grad school. My boss tells one about a cow on a tether attached to a point on the rim of a cylindrical silo of a given height and radius. You were supposed to calculate the grazing area available to the cow. I, being in a smartass mood (sarcasm is my ground state), ask, “Did you assume a spherical cow?” The didn’t-miss-a-beat response was, “No, I was able to use the point-cow approximation for this problem.” And I thought that was pretty funny, and something that works in a single-panel cartoon.


2 thoughts on “The Geometry of a Cow

  1. Pingback: World of Science News : Blog Archive : Spherical Cows [Uncertain Principles]

Comments are closed.