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January 24

Physical dimension of frequency per speed

in the formula x= ${\frac {\nu }{c}}$ where $\nu$ is a frequency and $c$ a speed what is the resulting dimension of x? Malypaet (talk) 10:13, 24 January 2024 (UTC)[reply]

Inverse length, 1/L. --Wrongfilter (talk) 10:21, 24 January 2024 (UTC)[reply]

Thank's, and for y=

{\frac {\nu ^{3}}{c^{2}}}

?

. Malypaet (talk) 11:52, 24 January 2024 (UTC)[reply]

1/(L²T). In units 1/(m² s), or something equivalent. I don't see any direct physical meaning for this combination.--Wrongfilter (talk) 16:10, 24 January 2024 (UTC)[reply]

Multiply by E as energy in joule and you get Watt per square meter, isn't it ?

But as there is a frequency in this equation, how do you tel Watt per square meter + something for indication the frequency, in system units or physical dimension? Malypaet (talk) 17:07, 24 January 2024 (UTC)[reply]

Perhaps the table and formula in the Irradiance article will help, especially since it has a section on the time-average of the component of the Poynting vector perpendicular to a surface. Modocc (talk) 17:59, 24 January 2024 (UTC)[reply]

I don't find anything satisfactory there. We often find watt per hertz with dimension

ML^{2}T^{-2}

which corresponds to the joule, as in electrical billing for KW-h where we remove the time. An electromagnetic wave is a flow of energy modulated in amplitude, therefore in the same unit of time an energy flow and a cycle flow. A power and a frequency which share the same unit of time, how to write it with x as energy value and y as cycle number in the frequency:

{\frac {x\ joule}{y\ cycle\cdot seconde}}

?

So, in the same fraction, one has the power and frequency value, and x/y gives the energy per cycle.

. Malypaet (talk) 22:08, 24 January 2024 (UTC)[reply]

I have no idea what you're trying to say here. I'll just point out that Watt per Hertz is not the same as Joule. Although both have the same dimension, they describe very different physical quantities (specific power vs. energy). This is an instance of the the confusion I warned about earlier (see below). — Where did you see the combination

\nu ^{3}/c^{2}

? --Wrongfilter (talk) 22:44, 24 January 2024 (UTC)[reply]

As a classic example of two very different physical quantities with the same dimension, take torque and work. Dimensions can be a useful tool, but they don't tell everything. PiusImpavidus (talk) 10:35, 25 January 2024 (UTC)[reply]

Yes but in my case, dimensions correspond to my feeling. I have an example with a constant flow of spheres of mass M crossing an area at speed c and all lines off spheres at the same frequency

\nu

Malypaet (talk) 14:02, 25 January 2024 (UTC)[reply]

Thank you all, this discussion allowed me to find my solution, even if it does not appear directly here. Malypaet (talk) 22:03, 25 January 2024 (UTC)[reply]

(edit conflict) @Malypaet: With (my simple way of showing) working: ⁠frequency (Hz)speed (m⋅s⁻¹)⁠ = ⁠s⁻¹m⋅s⁻¹⁠ = ⁠1m⁠. Bazza (talk) 10:28, 24 January 2024 (UTC)[reply]

A little bit of nitpicking: dimension and unit are not the quite the same thing. In connection with frequencies, this occasionally causes confusion. In this case, it might help to introduce a dimensionless (pseudo-)unit "cycles", so that frequency is measured in cycles per second, and the quantity x in cycles per meter (x is wavenumber). --Wrongfilter (talk) 10:39, 24 January 2024 (UTC)[reply]

@Wrongfilter: Thanks; nitpicking is always welcome as a bit of free education. My view of the world is not as precise as others', hence my inclusion of a qualifier on my response above. I had also linked Hz which conveniently gives its SI base unit equivalence (s⁻¹) in the first paragraph, but the link's not obvious. Bazza (talk) 10:49, 24 January 2024 (UTC)[reply]

Eo vs. Paleo prefix in geologic time

Why does the Eoarchean precede the Paleoarchean, but the Eocene follows the Paleocene?

Did the naming body (the ICS?) consider the inconsistency and disregard it, or not consider it at all? 140.147.160.45 (talk) 15:31, 24 January 2024 (UTC)[reply]

The term eocene was coined in 1831, 143 years before the ICS was formed. The term Eoarchean appears to have been used by Willem Nieuwenkamp already in 1965,^[1] also well before the genesis of the ICS. This must have been in his article "Geschichtliche Entwicklung der heutigen petrogenetischen Vorstellungen", Geol. Rundschau. 55: 460–478,^[2] presumably in the German form Eoarchaikum. It seems to me that the ICS gave its seal of approval to terms that were already widely used in the literature, with the senses as established there. This may have been a wise approach, similar to that of the king on the first planet visited by the Little Prince after biding his farewell to the rose. --Lambiam 22:53, 24 January 2024 (UTC)[reply]

(after ec)The epochs of the Cenozoic are named for the amount of "new" life (compared to the present day) that was present at that time. Eocene is the "dawn" of new life and the Paleocene is the old part of the Eocene, according to our article, a bit clumsy perhaps, but the names have been around for well over a hundred years. The Eoarchean is a much more recent coining, derived from "dawn" of the "ancient" (world), the very beginning of the Archean. The Paleoarchean is the "old" part of the "ancient", formerly it was the "early Archean". Mikenorton (talk) 22:56, 24 January 2024 (UTC)[reply]

What's the rarest level of human hospital?

There are probably many different classifications of hospitals for humans like teaching hospital, poison control center, Level I Trauma Center, burn center, state certified, AMA (or whoever does that) national accredited, maybe each board or subspecialty of MD and DO and the few paramedical degrees like nursing and podiatry have their own thing? Which has the fewest members? Sagittarian Milky Way (talk) 15:46, 24 January 2024 (UTC)[reply]

Might be a stand-alone ophthalmology hospital, if any still exist. Abductive (reasoning) 17:11, 24 January 2024 (UTC)[reply]

See Moorfields Eye Hospital. Alansplodge (talk) 18:28, 24 January 2024 (UTC)[reply]

Category:Eye hospitals has 50 articles, though obviously some might be not "stand-alone" or no longer exist. DMacks (talk) 18:31, 24 January 2024 (UTC)[reply]

Wouldn't the highest certification or accreditation or whatever they call it of eye hospital (I wouldn't know what that is) also include at least a few not just eyes hospitals like the Mayo Clinic? Sagittarian Milky Way (talk) 18:35, 24 January 2024 (UTC)[reply]

Having the criterion be "specialty hospital" vs. "department of a larger hospital", this a problem with the question. Even in that case, there are way more, say, children's hospitals than eye hospitals. Perhaps hospital ship is truly the rarest? Abductive (reasoning) 18:46, 24 January 2024 (UTC)[reply]

What would you classify as a hospital in this sense? In the US consumers get health services termed usually primary, express, urgent, and emergency. A "hospital" as a consumer thinks of in the US may sometimes only be defined as such if it offers emergency care, whereas the next level may be termed an urgent care clinic. However, the CDC and WHO definitions of hospital do not require emergency care. (I mention this all only because in the US this sense of scale can be a common consumer definition.)

Taking the CDC or WHO definition, there are several inpatient mental/behavioral health and physical therapy programs that may take place in an ordinary-looking house in an ordinary-looking neighborhood, where patients sit down to home-cooked meals at the table and do their own chores. This is different from a halfway house, but even the latter could/should/is be seen to be on the spectrum of specialized health care facilities (namely if there is any 24/7 medical/nursing/EMS staff). If your intended definition is open to these possibilities, the amount of unitary microscopically specialized care facilities may surprise you. SamuelRiv (talk) 18:48, 24 January 2024 (UTC)[reply]

I don't think the demarcation is so much whether it has an emergency room as whether it admits inpatients. --Trovatore (talk) 19:13, 24 January 2024 (UTC)[reply]

Ok. The WHO uses that in its definition. The AHA does not, nor do many subset classifications listed at the CDC. That's why I provided sources and asked OP for the definition they intended. SamuelRiv (talk) 19:27, 24 January 2024 (UTC)[reply]

Hmm? Your own link says According to the American Hospital Association (AHA), hospitals are licensed institutions with at least six beds.... --Trovatore (talk) 19:36, 24 January 2024 (UTC)[reply]

Unfortunately or not I've been infected with an American view that hospitals and standalone clinics, methadone clinics, doctors offices, simulated or real/converted houses, rehabs and nursing homes are different things. I've seen lists like this is the official list of all the poison control centers (some states having very few, obviously any hospital is better than no hospital but it's better to go to the poison control center if there's enough time or they're equal minutes away), these are all the burn centers and wonder which the country has the fewest of. Sagittarian Milky Way (talk) 20:09, 24 January 2024 (UTC)[reply]

I'm pretty sure poison control centers just take phone calls. Abductive (reasoning) 08:46, 25 January 2024 (UTC)[reply]

And would also wonder what's the fewest that's not that regional if the answer's something very regional like a certified gila monster treatment center or something, the only place that has gila monster antivenom 24/7/365. Sagittarian Milky Way (talk) 20:17, 24 January 2024 (UTC)[reply]

This is a bit of a digression, but our Gila monster article doesn't mention any such centers or even any such antivenom. It seems that bites are pretty rare, and rarely fatal even when they happen. --Trovatore (talk) 21:36, 24 January 2024 (UTC)[reply]

I don't know if such certification or antivenom exists. Searching snake antivenom center gives a top result of list of Hospitals with CroFab Antivenom. Quickly find hospitals near you that stock CroFab (crotalidae polyvalent immune fab). crofab.com so maybe there's no official list but CroFab will tell you who has CroFab. Sagittarian Milky Way (talk) 21:50, 24 January 2024 (UTC)[reply]

London is well endowed with specialist hospitals. There is a Royal National Orthopaedic Hospital in the west end, and the Royal National Ear, Nose and Throat Hospital near King's Cross (older directories switch "ear" and "throat"). Nearby is the Eastman Dental Hospital. 86.142.1.84 (talk) 09:53, 25 January 2024 (UTC)[reply]

Not forgetting the Hospital for Tropical Diseases, the Western Eye Hospital and the Royal Marsden Hospital which is a specialist cancer treatment hospital, as well as three children's hospitals. Alansplodge (talk) 14:56, 25 January 2024 (UTC)[reply]

According to Google we only seem to have dental clinics, a tropical clinic (New York Center for Travel and Tropical Medicine) and a New York Eye and Ear Infirmary but not just eyes. There's an orthopedic Hospital for Special Surgery, NYU Langone Orthopedic Hospital, Manhattan Eye, Ear and Throat Hospital (which I joked as a kid Eye, Ear, Nose, Mouth, Throat, Butt), Memorial Sloan Kettering Cancer Center (which is a hospital) and a few children's hospitals, one children's hospital even advertised(ses?) on over-the-air TV. Sagittarian Milky Way (talk) 23:51, 26 January 2024 (UTC)[reply]

<- I wonder how many high-security psychiatric hospitals there are. The UK seems to have 4 apparently. Sean.hoyland (talk) 10:15, 25 January 2024 (UTC)[reply]

Locked wards are a feature of all psychiatric hospitals, but of course patients who are not the subject of a detention order under the Mental Health Act are free to come and go at any time. The level of security varies. The highest is where the exit door is accessed by a corridor. There may be a handle on the outside allowing people to enter but no handle on the inside, meaning staff intervention is needed to leave. Opportunist patients may follow a delivery man out when he leaves, or, if conditions are right, vault the food counter and exit via the kitchen if it leads to the ward's outer door with handles on both sides. When a patient does this it leads to a meticulous search of the entire ward. 2A00:23C7:9C86:4301:6418:B7B2:105:23FE (talk) 10:30, 25 January 2024 (UTC)[reply]

To clarify, in the UK at least, "high-security" has a formal definition in this context and only 4 hospitals have that designation. Sean.hoyland (talk) 10:39, 25 January 2024 (UTC)[reply]

(edit conflict) There are three high-security psychiatric hospitals in England providing services to England and Wales: Ashworth Hospital, Broadmoor Hospital and Rampton Secure Hospital. There is one high security hospital in Scotland, the State Hospital in Carstairs providing services to Scotland and Northern Ireland. These four are equipped to deal with dangerous individuals such as Ian Brady ("Moors murderer") or Peter Sutcliffe ("Yorkshire Ripper"). Martin of Sheffield (talk) 10:52, 25 January 2024 (UTC)[reply]

Like the Magdalene Laundries in Ireland, psychiatric hospitals can be a dumping ground. A case history: [3]. 2A00:23C7:9C86:4301:6418:B7B2:105:23FE (talk) 10:50, 25 January 2024 (UTC)[reply]

People held in the "hospitals for the criminally insane" tend to be returned to prison. Peter Sutcliffe was last held at HMP Frankland in County Durham. 2A00:23C7:9C86:4301:6418:B7B2:105:23FE (talk) 11:16, 25 January 2024 (UTC)[reply]

No sooner had I pressed "Save" on the above edit than this appeared on the screen [4]. If AI is involved it's pretty impressive. 2A00:23C7:9C86:4301:DDA8:3416:7CEB:4CEA (talk) 11:30, 25 January 2024 (UTC)[reply]

No AI - laptops do unexpected things, and on this occasion it decided to access a link posted earlier. 2A00:23C7:9C86:4301:140E:5EAC:2D72:8A9E (talk) 13:12, 26 January 2024 (UTC)[reply]

It posted the above comment before I had even pressed "send". 2A00:23C7:9C86:4301:140E:5EAC:2D72:8A9E (talk) 13:14, 26 January 2024 (UTC)[reply]

In Australia we have Bush Nursing Hospitals. Wikipedia doesn't (yet) have an article on them, but they are mentioned in several, such as the one on Ian Turpie, a one time boyfriend of Olivia Newton-John. While there are only a handful left, there used to be many. They served as hospitals in rural towns. They employed nurses, but no doctors, and existed to service patients of the local doctors, who would visit to attend to those patients. HiLo48 (talk) 01:39, 27 January 2024 (UTC)[reply]

There's a standalone burn hospital in Poland's Siemianowice Śląskie, I think it's the only one of its kind in Poland, see website. --Ouro (blah blah) 16:17, 27 January 2024 (UTC)[reply]

(edit conflict) The words "hospital" and "clinic" appear to be interchangeable. Yesterday's Evening Standard reports:

The London Clinic opened in February 1932 after a group of Harley Street doctors set out to "establish a new kind of hospital that would set a standard of healthcare for generations to come."

If "clinics" are included the number of "specialist hospitals" (in Harley Street and elsewhere) is greatly expanded. News reports overnight say "Charles is doing well" and "the queen is by his side." While I wish him a speedy recovery, she is nothing of the kind. You may recall that a litigant filed a case in the High Court challenging her use of the title because English law specifically prohibits members of the royal family from marrying in register offices. The court office wrote back months later (target time for reply is five working days) to say the papers would be hurled into the wastebin if a court form declaring the case to have no prospect of success was not filed. Naturally they would hold on to the expensive court fee. The Civil Procedure Rules Committee examined the form and declared it to be a forgery. Also overnight it is reported that a jury has ordered Donald Trump to pay 83 million dollars in damages. His lawyer says she will appeal. Even Trump does not attempt to prevent his opponents having their day in court. 86.150.238.95 (talk) 16:37, 27 January 2024 (UTC)[reply]

Childrens' hospitals seem to be generalised [5]. 86.150.238.95 (talk) 16:37, 28 January 2024 (UTC)[reply]