Here's a table of water volumes at different temperatuers and
pressures. Yes, water does in fact compress as you raise the pressure
(no surprise here), but it doesn't compress by much.
temp F(C) 0 atm 500 a 1000 a 2000 a 3000 a
32 (0) 1.0000 0.9769 0.9566 0.9223 0.8954
68 (20) 1.0016 0.9804 0.9619 0.9312 0.9065
122 (50) 1.0128 0.9915 0.9732 0.9428 0.9193
A mile under water gives about 150 atmospheres of pressure, so that
should be less than 1 percent compression, according to the table.
What you probably saw on the show was an effect of the trapped air
in the leaky capsule rather than the water. The "empty" capsule was
really full of air, and as water leaked into the capsule at high
pressure, the air got squeezed into a tiny little space. When the
capsule was brought back to the surface, the air expanded and pushed
the water out, shooting it far across the deck for a longer time than
if there was just water in the capsule.
Tom J. (w mike)
(published on 10/22/2007)
