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Re: A TRUE/FALSE question for your kids



On Wed, 28 Jan 1998, LUDWIK KOWALSKI wrote:

A boat is floating in a small swimming pool and the occupant drops a large
rock into the water. Will the level of water in the pool rise, fall or
remain the same?

Only one prediction is TRUE. It can be validated in a laboratory by using
a plastic cup floating in a beaker. You would probably use the word CORRECT
(instead of TRUE) John M. What is the difference?

I think "correct" and "true" are pretty much synonyms and I'm happy with
either here. It certainly *is* true that the water level drops (assuming,
of course, that the rock has a density greater than that of water, that it
doesn't have a large air cavity, that you don't just dangle it from the
anchor line, that the water is deep enough to begin with, and so on.)
There is an important difference, however, between an observational fact
and a scientific theory.

John
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