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#5: P(max) vs. P(min) ?




Now we can look into practical considerations.

As we determined, P(max) for any wood species is the pressure needed to sink it permanently. In the real world, pressurized wood can be dropped in water and will sink all the way to the bottom, even the deepest ocean. The pressurization to P(max) can be done on land, or on a boat.

But....in the ocean, there is no need to pressurize P(max) to sink wood. Water supplies its own pressure. For example, in the chart above, the P(max) for Pine is 1250 PSI.  This pressure naturally exists at 2500 ft depth.  So, if we bring Pine wood to 2500 feet below the ocean surface, it will simply sink permanently.

But wait !  We don't even need to go all the way up to P(max) when we are already in the ocean. We can just go to P(min).

Indeed, if we bring pine wood to the depth of 360 ft, corresponding to its P(min) of 150 PSI; it will start to sink.  Once it starts to sink deeper, the pressure will get higher. So it automatically reaches P(max) and is sunk forever.

We will continue looking into P(min) in the next few posts.