On May 1, 2:50 pm, Jim Logajan wrote:
toad wrote:
I can't tell if you are a crank or just a nit-picker.

What practical difference is there between:

Standard statement:
"The air in a thermal rises because it is hotter and less dense than
the air around it."

Your rule:
"The air in a thermal rises because it is displaced by the denser,
cooler air around it."

Absent gravity, of course neither statement is accurate. Include gravity
and the second statement is perhaps more conceptually useful though still
begs the question. All air gets pulled downward, but less dense air is
forced to rise because it is "squeezed" upward by the more dense air around
it. I think that is perhaps conceptually even more "accurate".

I had pretty much assumed that we were including gravity :-)

Todd