3 ms·
> a place so deep that its exterior pressure would feel like having five jumbo jets parked on your chest I had to check the maths on this, but it looks good:
by dmurray 7y ago
> a place so deep that its exterior pressure would feel like having five jumbo jets parked on your chest
I had to check the maths on this, but it looks good:
- My chest (upper torso, diaphragm to shoulder blades) is about 30cm * 40 cm, or one eighth of a square meter
- The sub goes down 35,000 feet, or 11,000 metres. So that's 1,400 cubic metres of water above my chest. Water is virtually incompressible even at that depth, so that weighs 1,400,000 kg.
- An empty 747 weighs 373,000 pounds or 170,000 kg [0]. At maximum takeoff weight, up to 400,000 kg [1].
That means the equivalent of between 3 and 8 jumbo jets above my chest.
[0] http://www.aerospaceweb.org/question/planes/q0051b.shtml http://www.aerospaceweb.org/question/planes/q0051b.shtml
[1] https://en.wikipedia.org/wiki/Boeing_747-400 https://en.wikipedia.org/wiki/Boeing_747-400
- subpixel 7y agoOdd unit of measurement, as I assume jumbo jets are manufactured to be as light as possible.
- throwaway_pdp09 7y agoThe correct unit is the Whales. 3 to 8 times the size of Whales.
- markdown 7y agoI only understand weight in olympic swimming pools.
- willvarfar 7y agoAn El Reg unit of measurement, no? Oh the nostalgia!
- throwaway_pdp09 7y agoEl Reg? No... Pretty much an ISO standard by now...
- ethbro 7y agoAt what temperature and altitude?
- TrainedMonkey 7y agoSince we are doing math and all, area of Wales is 20,740 km^2 ^1, this gives average weight per m^2: 0.0000675024 kg / m^2 = 1400000 / 20740000000 Now then, per ^2 soil weights between 1200 and 1700 kg per cubic meter. Let's take upper estimate to account for constant rain and minor human infestation in Wales (weight of cubic meter of concrete is 2400 kg ^3). This gives depth of Wales that equals to the pressure experienced by dmurray's chest of 0.0000000397 meters of ~40 nanometers. That is greater than feature size in modern CPU's... Well, there you go folks, I dare say that is a more useless (and maybe more fun too?) comparison than comparing pressure with jumbo jets. ^1 - https://www.google.com/search?client=firefox-b-1-d&q=wales+area+in+m%5E2 https://www.google.com/search?client=firefox-b-1-d&q=wales+a... ^2 - https://www.reference.com/science/much-cubic-meter-soil-weigh-e48660fa83d913ab https://www.reference.com/science/much-cubic-meter-soil-weig... ^3 - https://www.google.com/search?client=firefox-b-1-d&q=concrete+weight+per+meter https://www.google.com/search?client=firefox-b-1-d&q=concret...
- throwaway_pdp09 7y agoWhales. Not Wales. Mass, not area. Far more plausible and chosen for the oceanic theme.
- kingofpandora 7y agoThe chance that TrainedMonkey did this unintentionally is 0.0000000397%.
- HeyLaughingBoy 7y agoBut they're still heavy, relative to everyday items. Dumb anecdote: I once made a comment to a co-worker about handling hay bales. When I pointed out that the ones I needed to move weighed around 1,600 lbs his amazement was palpable: "Seriously? Grass shouldn't weigh that much!"
- RandomBacon 7y ago> Water is virtually incompressible even at that depth, so that weighs 1,400,000 kg. Even if it was compressible, it would still weigh the same.
- dredmorbius 7y agoThe pressure is determined by the mass of the water column above you. If water were compressible (as air is), that mass would vary by depth, complicating calculations. As water compresses minimally, density is constant, and computing based on area and depth at 1000 kg/m^3 is sufficiently accurate.