They are crushed
It is most likely that they have adapted to the extreme pressure.
There is greater pressure the deeper you go in water. So if you go too deep, the pressure in the human lungs will be so great and too much that the persons lungs will collapse.
When you conduct the hot soda can in cold water experiment, the sudden change in temperature causes the air inside the can to cool and contract, creating a lower pressure inside the can. This lower pressure causes the can to be crushed or implode due to the higher pressure of the surrounding atmosphere pushing on the can.
You have to fill the can with steam and then seal it closed. when you then put the can in cold water the steam will condense into water and the can will be crushed by atmospheric pressure.
Just like gases, water exerts pressure due to its weight, and this pressure increases with depth. As a submarine descends, the water pressure surrounding it intensifies, which can be fatal if there are structural weaknesses in the hull. If these weaknesses are not addressed, the immense pressure can cause the submarine to be crushed, compromising its integrity and safety. This is why submarines are designed to withstand significant underwater pressure.
The air pressure inside our bodies balances the external air pressure, preventing us from being crushed. Our bodies are also designed to adapt to changes in pressure, allowing us to withstand variations in atmospheric pressure without harm. Additionally, the human body is mostly made up of water and solids, which are not easily compressible.
A can containing a small amount of boiling water is filled with water vapor and very little or no air. When cooled quickly, the water vapor condenses into a few drops of water, leaving a partial vacuum in the can. Air cannot enter the can thru the small opening fast enough to equalize the internal pressure with the external atmospheric pressure, and it is crushed by atmospheric pressure.
If you put pressure on ice it will melt.
Salt water has a higher density, so the pressure at a given depth increases.
The vapor pressure of water decreases when mixed with sodium chloride. This is because the presence of sodium chloride particles in the water lowers the vapor pressure of the solution compared to pure water at the same temperature.
there is too much water pressure so it will be crushed under all the weight.
It increases.