Wikipedia:Reference desk/Archives/Science/2021 September 11

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September 11

Which ship would be drowned faster in case of raging / stormy sea?

Which ship would be drowned faster in case of raging / stormy sea, a ship that has a heavy load or the similar ship that has lighter load? I'm not sure if a load plays a positive role in such a situation or not.--ThePupil (talk) 00:07, 11 September 2021 (UTC)

The Book of Jonah says heavier but take that with a grain of salt. Completely different technologies from that fable. Sagittarian Milky Way (talk) 01:14, 11 September 2021 (UTC)

Larger vessels, be they in the sea or the air, can usually handle storms better than smaller ones. ←Baseball Bugs ^{What's up, Doc?} carrots→ 02:23, 11 September 2021 (UTC)

The question was about similar ships, not smaller and larger ones. Cargo ships are designed to be able to operate in a "raging/stormy sea" if necessary: if they sink it's because something went wrong, for example a hatch cover breaking or coming unlatched, leading to flooding of a hold. Further, a lightly loaded ship may contain ballast that would affect the scenario. I don't think it's reasonable to speculate about specific possibilities: there is too much room for variation. --184.144.99.72 (talk) 04:37, 11 September 2021 (UTC)

The most likely doom scenario in a storm is the ship capsizing, which can happen if it is hit broadside by a large wave. The stability of the ship is related to the height of the centre of mass of the vessel together with its load. Relative to the height of the centre of mass of the unloaded vessel, the centre of mass of the loaded vessel will be higher if the load is all on deck, and lower if stowed in a below-deck cargo hold. So depending on how the ship is loaded, it may be less stable or more stable than when carrying no load. If the vessel is designed to be self-righting, a lower centre of mass (on the upright vessel) also supports its righting after capsizing, while a top-loaded ship, even if designed to be self-righting, may not overcome the capsizing – which can also be triggered by the load shifting on deck if it is not securely stowed. Capsizing does not necessarily imply that the ship will sink; the air that remains trapped, as well as any cargo whose density is less than that of the surrounding water, may provide enough buoyancy to keep it afloat.  --Lambiam 08:56, 11 September 2021 (UTC)

With a heavier load, the ship will be deeper in the water, with a smaller freeboard. That means that it will take smaller waves or list before the water washes over the deck, endangering the ship. Most capsizing ships suffered from shifting cargo, moving the centre of mass sideways, giving positive feedback to a list. Also see free surface effect. If the cargo holds are empty, this can't happen. If the cargo holds are full by volume, this can't happen either, but if full by mass well before they are full by volume (dense cargo), shifting cargo can be a large contributor to sinking. The cargo also increases the moment of inertia of the ship, but what effect this has on safety depends on the details. PiusImpavidus (talk) 10:38, 12 September 2021 (UTC)

Why can't they make the decks slightly sloped to a wall-less edge railing for drainage, the doors, bridge, inside etc watertight and anything that can't be put on snorkels? Similar to how modern lifeboats look more like enclosed pods than open rowboats. Sagittarian Milky Way (talk) 03:32, 14 September 2021 (UTC)

Whaleback--Verbarson (talk) 11:18, 18 September 2021 (UTC)

What's the point of poison fruits ?

What's the point of poison fruits if its main aim is to spread seeds by birds/animals? Rizosome (talk) 00:30, 11 September 2021 (UTC)

Most fruits have been evolved to be consumed by one or a few particular species, to whom they are not poisonous: a given substance can be non-poisonous (or distasteful) to some species of birds or animals, but poisonous (or distasteful) to others such as humans. Fruits that are poisonous to humans are not poisonous to the species that normally eat and thus propagate them in the wild.

Until very recently, in evolutionary terms, humans were so few in number compared to other species of animals and birds that it is unlikely any fruit evolved by natural selection to be non-poisonous specifically to humans. However, since agriculture was invented, humans have selectively bred some fruits, a process called artificial selection, to make them less or non-poisonous. Also, some fruits poisonous to humans in an unprepared state may be rendered edible by various methods of preparation. {The poster formerly known as 87.81.230.195} 90.200.67.3 (talk) 01:07, 11 September 2021 (UTC)

A great example is poison ivy. Although the urushiol is quite toxic to most people, birds can eat the berries with impunity. A similar example is with fruiting bodies that contain capsaicin (e.g. hot peppers) - the hot spice is meant as a deterrent, but again it is not detected by birds at all, who eat it without sensing the heat. As our article notes, in the wild, birds are the primary means of seed transport. On the other hand, we can eat chocolate with impunity while many mammals suffer from theobromine poisoning if they do. Matt Deres (talk) 14:38, 13 September 2021 (UTC)

Strictly speaking, urushiol isn't toxic in the sense of being poisonous (so "poison ivy" is a bit of a misnomer) - instead, it causes harm by producing a damaging allergic reaction. PaleCloudedWhite (talk) 21:00, 13 September 2021 (UTC)

Bear in mind that there is no "point" to evolution. It's a natural process. ←Baseball Bugs ^{What's up, Doc?} carrots→ 11:27, 11 September 2021 (UTC)

For "point" read "advantage". —Tamfang (talk) 01:37, 14 September 2021 (UTC)

By happenstance, not by conscious design. ←Baseball Bugs ^{What's up, Doc?} carrots→ 04:34, 14 September 2021 (UTC)

Which I think is covered by definitions 4.3 to 4.4 here. Iapetus (talk) 08:32, 15 September 2021 (UTC)

See also I have always wondered: why are some fruits poisonous?. Alansplodge (talk) 16:43, 11 September 2021 (UTC)

Lewis acids/base questions.

What are some examples of Lewis acids with basic pHs? Googling Lewis acids with basic pH didn't return anything that specific. So it recently occurred to me that Lewis bases can have acidic pHs, an example is hydrogen peroxide. Although hydrogen peroxide could be an Arrhenius acid, in actuality it is unstable in alkaline solutions rendering it not happening. So hydrogen peroxide is more of a Lewis base than a Arrhenius acid (thus Lewis acid). But its pH is in the weak acid range. Are there any other examples like this, as well as Lewis acids with weak-base pH? Thanks. 67.165.185.178 (talk) 05:38, 11 September 2021 (UTC).

Are you asking about amphoterism? DMacks (talk) 15:28, 11 September 2021 (UTC)

Sure. Should amphoterism be mostly about something that can be a Lewis acid and a Lewis base, or say, a Lewis acid and a Arrhenius base, and Lewis base and a Arrhenius acid? 67.165.185.178 (talk) 15:53, 11 September 2021 (UTC).

Aluminium hydroxide is a Brønsted–Lowry base, so an aqueous solution of it would have a high pH, but it also acts as a Lewis acid. --OuroborosCobra (talk) 21:40, 11 September 2021 (UTC)