"Jeff Morris" wrote
[snip]
So take your pick, either explanation works, and I'm sure there are
others. However,
I hope you can appreciate that explanations like "gravity creates the
inner bulge,
centrifugal force creates the outer bulge" makes physicists wince!

Yes, I can, as I've watched my physics teaching partner wince quite a bit
this week as we discussed this thread. He was quick to cover our whiteboard
with formulas and drawings. It's an interesting thread though, and
notwithstanding my oversimplified analogies, I've learned a lot from it. By
the way, I saw that same wince from a black history professor when I
suggested that the Civil War was fought to free the slaves, and then again
when I suggested to an ancient lit professor that The Odyssey has all the
earmarks of an Arnold Schwarzenegger movie. Probably explains why I like a
good fart joke.
Scout