I think there's a flawed assumption in that logic: if you consider the car's descent as a result of gravity (and conversely drag created by fluid resistance) and we consider a reference frame relative to that motion, then I believe your original logic would have us assume that the car falling motionless in a reference frame relative to the aforementioned reference frame. (for the sake of simplicity, assume the drag force counteracts the gravitational force such that the resultant velocity is constant and thereby workable using inertial reference frames). Point being, if the car is moving (spinning, twirling) relative to its descent then having the passengers "free" themselves might cause them to become dislogdged, disoriented, and potentially injured. However, I agree, that a plan should be made (possibly long before the crash) and that each person should be ready to execute that plan before anyone attempts to evacuate the car.Tups wrote:If there's other people in the car, make sure that they have at least freed themselves from the seatbelts and know what you're about to do before you open or break anything. Of course, if you're those "every man for himself" type of guys, don't mind the others.
Here is an interesting point, one I had not considered and one I cannot easily dispute. The question is, even if the crashing smack dab on the surface of what would soon be be a mile long descent into the ocean, would a broken window or an open door invite dangerous amounts of pressure or fluid into the cabin? If this were the case, even if landing on the surface of the ocean somewhere deep in the heart of the ocean (where there is arguably endless amounts of water), then certainly the prognosis only gets worse as the car sinks (as the atmospheric pressure increases).Tups wrote:Yeah, the water outside the car is pressing the door against its frames, so it's nearly impossible to open it until the pressure difference over the door is close to zero, i.e. the car is filled up with water. However, until then there's an air pocket that allows you to breathe and carefully plan your escape from the metallic coffin, so there's really no need to break a window, possibly get seriously injured when the water rushes in and risk capsizing the car. Except if you're driving a POS Vauxhall. Then GTFO ASAP
One question all the literature or videos I've read haven't answered is this: assuming a person crashes deep in the heart of the ocean, again where there's arguably endless amounts of water and the depths are impassible, and assuming the person is able to "punch" the window before sinking just 10 feet into that water without being crushed or harmed by both the water and the glass shareds, then the question is: will that person be able to swim to surface as the car continues to sink? I ask this question because I wonder if, combining my partial understanding of Pascal's principle and Archemede's Priciniple, I would think that the displaced water, whose equilibrium had been upset, its naturally tendency to revert to equilibrium would force that water to fill the void above the car (a void that the car had filled just moments before it sank to its new current location) and therefore the swimmer would need more "energy" than the kinetic energy of the displaced water seeking equilibrium (meaning -- the swimmer is doomed).
This wasn't an attack on you Tups, so I trust you didn't take it that way. I'm glad you brought up the points you did, I haven't heard them elsewhere, and they've forced me to reconsider my emergency plan. Unfortunately, I no longer have one, and I'm more glad about that than I am upset (because my previous one would've killed me).
I'm just totally and utterly stumped and trying to work this out logically the best way I know how. I only have 2 semesters (4 at some other colleges) worth of classical physics so my understanding is feeble at best. I just want to know what I should do -- if anything -- to survive such a catastrophy if I should ever, heaven forbid, find myself trapped by it.