this post was submitted on 18 Sep 2024
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Followed shortly by ‘oh shit’ and ‘we dropped two weights’ then ‘guys, it’s getting kind of wet in here…’
Just kidding, mostly.
Serious question: how does a submarine know how much it weighs?
Explosive decompression is almost instantaneous at that depth. They wouldn't have had a chance to even blink.
Implosive compression?
Wouldn't it have happened so fast that they never even registered the pain of being crushed? Like, the signal from the body never even reached the brain, it was so fast.
So fast they'd not even be able to register what was happening. Not a bad way to go.
I'll take dying in my sleep for 100 Alex.
No joke, I was in the hospital with a heart attack back in January, waiting on my stent.
Woke up at 6 AM and was fiddling on my phone such as you do. Nurse comes in:
"Were you asleep about an hour ago?"
"Yeah, why?"
"Your heart stopped for 8 seconds."
"Um... thank you? I'm not sure what to do with that information..."
I never really got the “heart stop = dead” thing like yes, if you’re heart stops you’re going to die, but even when someone is beheaded, they are still conscious enough for a few seconds to blink their eyes in response to questions. It’s when the electrical signals in your brain stop that you’re actually dead, not your heart.
Yup! I love the whole pro life "abortion stops a beating heart!" thing. The heart doesn't really mean much, you can make a heart beat in a petrie dish, that doesn't make it "alive".
https://www.theguardian.com/science/2014/feb/02/stem-cell-research-heart-disease-long-qt
Doubly backwards
Yeah, it was definitely intended as ~~humor~~ an attempt at levity.
That's when your spaceship shreds apart.
https://m.youtube.com/watch?v=j8XgLX5FLdY
Yeah, the ocean was decompressed by a tiny bit..
I assume that the submarine producer gives stats like empty weight from which the current weight can be calculated.
However, weight isn't the important thing in a sub. It's the weight to volume ratio, or buoyancy.
A sub sinks when buoyancy is negative and rises if the buoyancy is positive.
There are three common ways to achieve the changing buoyancy: the most simple one is a vessel with positive buoyancy adding droppable weights until the buoyancy is negative.
Other ways are a neutral buoyancy vessel that uses it's engine power to push itself up or down. Or a vessel that can change it's buoyancy by filling up tanks with water (to reduce buoyancy below neutral) and blow them out with air or other gases lighter than water (to raise buoyancy above neutral). A combination of several methods is also possible.