this post was submitted on 18 Sep 2024
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[–] sramder 8 points 2 months ago (2 children)

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?

[–] just_another_person 36 points 2 months ago (6 children)

Explosive decompression is almost instantaneous at that depth. They wouldn't have had a chance to even blink.

[–] [email protected] 26 points 2 months ago

Implosive compression?

[–] [email protected] 13 points 2 months ago (1 children)

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.

[–] just_another_person 20 points 2 months ago (1 children)

So fast they'd not even be able to register what was happening. Not a bad way to go.

[–] snausagesinablanket 10 points 2 months ago (1 children)

I'll take dying in my sleep for 100 Alex.

[–] jordanlund 21 points 2 months ago (1 children)

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..."

[–] Supervivens 7 points 2 months ago* (last edited 2 months ago) (1 children)

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.

[–] jordanlund 8 points 2 months ago

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

[–] sramder 4 points 2 months ago* (last edited 2 months ago)

Yeah, it was definitely intended as ~~humor~~ an attempt at levity.

[–] Hule 3 points 2 months ago

Yeah, the ocean was decompressed by a tiny bit..

[–] CrayonRosary 2 points 2 months ago

Explosive decompression

Doubly backwards

[–] [email protected] 9 points 2 months ago

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.