#units of measurement

[victusinveritas]

[enuode-au]

About Writing Heights

Height is measured in blocks and pixels. As stated in the previous measurements post, one block is a meter tall, and a pixel is 5% of a block, or 1/20th of one. Let's take a look at an example:

Lizzie is 10'1, or about 307cm tall. So that's three blocks and one-and-a-half pixels tall. How's that gonna be written?

We write it as 31.5, or "3-subscript-1.5". The block number is always the first number, and the pixel number is second, written in a subscript format, rounding to half a pixel (intervals of 0.5).

We say it as "three one-and-a-half". In settings in which height usually resides within one block range (such as between one and two blocks), such as tight-knit communities of similar race individuals, the block may be cut off entirely. However, in the case of the rulers, it's good to add the block to the number out of formality.

[myprivatelibrary]

I finally make it to the ladder. I stumble forward and grab one of the rungs. I'm just so weak. How am I going to climb a 10-foot ladder? Ten-foot ladder. I think in imperial units. That's a clue. I'm probably an American. Or English. Or maybe Canadian. Canadians use feet and inches for short distances. I ask myself: How far is it from L.A. to New York? My gut answer: 3,000 miles. A Canadian would have used kilometers. So I'm English or American. Or I'm from Liberia. I know Liberia uses imperial units but I don't know my own name. That's irritating. -Project Hail Mary, Andy Weir, p. 12-13

[dat-physics-boi]

A barn-light-eon is about a liter.

I don’t know what to do with that information.

1 barn * 1 eon * 1 speed of light = 0.94 liters

**(barn being a tiny cross sectional area, and an eon is a billion years)

[anonymousqueenofrandom]

Apparently we have a new unit of measurement.

Canadian Geese.

I have so many questions!

[word-for-today]

Word for today: Bubnoff Unit

A unit used by geologists to describe the speed of erosion; one Bubnoff equals one cubic meter of earth moving one meter per million years, or one micrometer per year.

[supertrainstationh]

Working form scratch doing elaborate town-building from using absolutely nothing but GIMP and satellite photos, and insisting that every single building, road and sidewalk be true to scale on the map, has gotten me more comfortable with the use of meters as a unit of length than any other experience in my life.

[futurebird]

Stop using "the bomb at Hiroshima" as a unit of measure for the love of all that is decent.

Can pop science writers, documentarians, and science show makers PLEASE stop using "the bomb at Hiroshima" as a unit of measure?

It's just unsettling and at worst sounds like the worst kind of jingoism (if the show is US made), at best tone deaf.

Use an atomic test, or Mt. St. Helen or Tunguska, or "tons of TNT" -- just anything else will do.

The worst is when it's treated like a plural noun. "200 Hiroshimas!" If could never hear that again it would be awesome.

[semantic-alchemy]

one BTU per second is not quite equal to sqrt(2) horsepower

[pleasetakethis]

“Americans will use any unit of measurement except the metric system!”

[victusinveritas]

[enuode-au]

Units of Measurement [1]

LENGTH, TIME, TEMPERATURE

Length

Pixel [px] - Smallest Unit (0.0625m, 0.21ft/2.46in)

Block [bl] - 16 pixels (1m, 3.28ft)

Chunk [ch] - 16 blocks (16m, 52.49ft)

World [ow] - 16 chunks (256m, 839.89ft, 0.16mi)

Border [bo] - 16 worlds (4096m, 13438.32ft, 2.5mi)

EXAMPLE:

Earth has a circumference of 40,075,000 meters (aka blocks).

This means that it has a circumference of 2,504,687.5 chunks, 156,542.97 worlds, and 9,783.94 borders.

NOTES:

There's no inches, centimeters, miles, whatever.

No one knows why the abbreviation for "world" is [ow] and not [wo]. In reality, it stands for Old World.

No one knows where the term "border" came from. In reality, it came from the existence of world borders, and how borders can have extra space beyond them.

Time

Tick [ti] - Smallest Unit

Second [sec] - 20 ticks

Minute [min] - 1,200 ticks

IGD [igd] - 24,000 ticks, 20 minutes

Hour [hr] - 60 minutes

Day [dy] - 24 hours

Month [mon] - Varies

Year [yr] - 365 days (no leap years)

NOTES:

No one knows why IGDs are called what they are. In reality, it stands for In-Game Day.

Temperature

Degrees [deg] - Sole Unit

EXAMPLE:

Biome temperature ranges from -0.7 to 2.0. Multiplying that by 16, and then 16 again, makes the temperatures go from -179.2 to 512.0 degrees. 26deg (~74F) is an average temperature.

The highest temperature on the scale is 512deg (1461F).

The lowest temperature on the scale is -179.2deg (-511.47F).

Freezing is 11deg, and boiling is 74deg. Average human body temperature is 34.5deg.

[somethingusefulfromflorida]

Age: 656 fortnights

Height: 1.02777 fathoms

Weight: 3⅓ firkins (American dry firkins, not British cheese or wine firkins, let's be realistic here)

[josiebelladonna]

okay, so i haven’t seen this anywhere on tumblr (which on its own astounds and terrifies me), but here are some units of measurement for radioactivity:

the Becquerel

Becquerel measure the decays per reciprocal second of a substance. 1 Bq = 1 s^-1 a reciprocal second is the multiplicative inverse of a second. this is done to avoid fatal errors when in comparison to 1 hertz, which is very similar but not the same. 1 ms−1 would mean 10^6 disintegrations per second: 1·(10−6 s)−1 = 10^6 s−1, whereas 1 microbecquerel would mean 1 disintegration per 1 million seconds. every million seconds, or 11 and a half days, you have a single disintegration of the material and further release of ionizing radiation (it sounds confusing, but it’s not).

in relation to the Curie, which is the measurement of decays on the basis of radium, given madame curie and her husband discovered it, the Becquerel is as follows:

1 Ci = 3.7×10^10 Bq or 37 GBq (gigabecquerels)

and 1 Bq ≅ 2.703×10^−11 Ci ≅ 27 pCi (picocuries)

the prefixes, by the way, because i know those can be confusing, especially when you go beyond 1 trillion: kilobecquerel (kBq, 1000 becquerels), megabecquerel (MBq, 1 million), gigabecquerel (GBq, 1 billion), terabecquerel (TBq, 1 trillion), and petabecquerel (PBq, 1 quadrillion). 

in the opposite direction: decibecquerel (dBq, 1 tenth), centibecquerel (cBq, 1 hundredth), millibecquerel (mBq, 1 thousandth), microbecquerel (μBq, 1 millionth), nanobecquerel (nBq, 1 billionth), and picobecquerel (pBq, 1 trillionth).

i’ll spare you the mathematical calculations to determine the level of radioactivity because i’ll just put everyone to sleep, but for some examples: our bodies contain potassium-40 and carbon-14 (in very small amounts, but they’re there nonetheless). the former decays at 4,430 decays per second. sounds like a lot, but since it’s per aperiodic event per second (i.e., it’s a ratio), and it’s trace amount of potassium (0.0169 g to be exact) with a half-life of 1.277 x 10^9 years, we can calculate it at <30 becquerels. it’s not nothing, for sure, but it’s nothing compared to like... say, the hiroshima bomb which was 8 yottabecquerel (8 septillion becquerel) with a yield of 16 kilotons. for drinking water, because radioactive elements simply exist in nature, the level should be at least 0.185 Bq/liter (5.0 pCi/L). surface water in say, a lake, should be anywhere from 0.0037 - 0.0185 Bq/liter (0.1 - 0.5 pCi/L)

the higher the becquerel (or picocuries for that matter), the more radioactive.

the Becquerel was introduced in the 70s to more accurately represent the magnitude of decays (prior to then, we had the rutherford, which was 1 megabecquerel).

the Coulomb per kilogram

i learned about the coulomb when i was initially studying mechanics in high school: it measures the quantity of electrical charge in 1 second through 1 ampere, or amp. all i’m going to say about amperage is that it’s the thing about electrical charge that can prove to be fatal if it’s high enough (you can get hit with 1000 volts and, while it might hurt a little, it won’t kill you. however, 1000 volts backed up with 200 amps... yeah, you will end up in the hospital with a third-degree burn, no doubt about it).

this one is more for the level of exposure: 1 roentgen is equal to 2.58 x 10^-4 Coulomb per reciprocated kilogram of air. not solids, air. 1 roentgen is equal to 2.58 Coulombs of electrical charge per 10000 kilos of air. (*jamie hyneman voice* well, now there’s your problem!)

the Gray

simply put, dosage. it’s absorption of 1 joule (or 1 kilogram per square meter every reciprocated second) of radiation per kilogram of whatever matter there is.

for perspective, the radiation you get from a ct scan is 6 mGy (6 milligrays, 6 thousandths of gray) or 14 mGy. whereas, the dose applied from chemo-radiation varies wildly: to cure the cancer, it can go from 20 Gy all the way up to 80. in preventive cases, it can be <2 Gy.

it’s a vital role in dosimetry and the only equation i’ll give is the conversion because it’s going to get a little sideways from here:

1 Gy = 1 joule/kilogram which in turn equals to 1 meter squared/1 second squared

in the horrific, grotesque, phantasmagoric, utterly nightmarish realm of radiation poisoning, the gray will show the severity of the disease, granted they are certain to happen when exposed to high amounts of radiation (compared to the probability on the lower tier). 5 gray is, for the most part, the l.d. 50: the little girl in the goiania accident of 1987 was exposed to 6 gray, whereas her father was exposed to 7 and yet he survived it - he eventually died in 1994 from drinking, but he survived something that would otherwise kill a 75-kilogram/165-pound person. some of the men who went into chernobyl unprotected were exposed to 5 gray in like a couple of seconds (some of the dosimeters didn’t even work properly, either!) ebenezer byers, a golfer who fucked up his arm, was prescribed radithor (radium water) by william bailey and drank 1400 bottles of it - i’m gonna tell you this right now, that story + the story of the “radium girls” are very graphic, so don’t read them if you’re easily triggered. bailey also died about 10 years after byers in the 40s: both men had to buried in lead-lined coffins. both were exhumed and both were described as having been “ravaged by radiation.” 20th century quackery at its absolute dumbest.

the Rad

that’s rad! the rad is basically to gray as the curie is to the becquerel. it’s 0.010 gray.

(we use it here in the states but chapter 5.2 of the guide to the SI discourages it.)

but like the gray, it’s used in dosimetry: when i was reading about the nevada test site the other night, i came across a map that shows the amount of absorption in the wake of the fallout from the blasts. here on the west coast, we were away from the fallout just by the nature of the wind. downwind from the test site in st. george and southern utah, where they bore the brunt of it, sustained continuous absorption of more than 100 rad. less than 100 is survivable. blood might be kind of wonky, but you should be okay. 100 to 200, still survivable but you might barf and feel like you just got kicked in the crotch. 200 to 1000, prognosis negative. (l.d. 50 is 400) 1000, goodbye friend. (weird when i say that chemo-radiation is 4000 rad like bruh)

the Sievert

this is where it gets a little convoluted and i had to read this one twice to get it. where gray is simply absorption, the sievert is the dose quantity or effective dose.  “aren’t they the same?” you might ask. nope. not even.

effective dose adjusts the absorption for radiation type and relative to biology, i.e., it tells us about the future and if any complications will arise from it. it’s the biological effect of 1 gray - hence why i believe if you read about any of this stuff, you cannot. c a n n o t. can. not. EVER. let hysteria and fear get the best of you. you have got to approach it levelheaded and really look at the numbers and the measurements when held next to biology.

context is important, and it’s especially important in nuclear science.

so with this in mind, radiation is naturally occurring. just by nature of planet earth and where we are in space, it makes sense that we do in fact receive very incremental, very harmless doses of radiation. because of this, the sievert is more often than not measured in incremental doses.

quick side-note: electronics do emit radiation, but it’s not ionizing, though. your laptop, phone, tv, microwave, anything that has electronics in it, radio towers, light switches, all of it, will set off a geiger counter simply because of their nature, not because they’re emitting alpha particles: so they’re completely harmless. for simplicity's sake, we’re looking at ionizing radiation, the kind that can do damage as it knocks electrons off molecules and atoms (hence the name).

your typical banana, healthy, delicious, packed with potassium and vitamins that you need for your muscles and bones, contains 98 nSv (nanosieverts). also, fun fact: there’s actually an illustrative unit that uses the banana as a means of measurement. it’s called the banana equivalent dose! who says nuclear scientists don’t have a sense of humor?

on average per year, the general public is exposed to 1 mSv (1 millisievert). conspiracy theorists, start your engines!

your average ct scan will expose you to 10 to 30 mSv, while someone who lived near fukushima in march 2011 was exposed to 68 mSv.

someone who chronically smokes will expose their lungs to 160 mSv - apparently cigarettes contain polonium-210 and lead-210. as if you need any more reasons not to smoke.

1 Sv is reserved for astronauts. the hiroshima bomb released 5 Sv. the people at goiania received 4.5 to 6 Sv. doctor louis slotin of the manhattan project received 21 Sv (talk about graphic, holy hell). cecil kelley received 36 Sv (AJKDSLSJKLDSJSDKL). i forget what chernobyl was but it was up there.

and then you have dose rate per year and also per hour.

we’re often exposed to 2.4 millisievert per year or 270 nanosievert per hour on average. the trinity test released 190 mSv/h (measured 20 miles away 3 hours after the fact).

and before you ask, i sleep very soundly at night. i’m not a certified nuclear scientist (my grandpa was, but i’m not): i’m just someone who has geeked out over this stuff most of her life, and i wrote this in the wake of that tiny capsule of cesium-137 going lost in australia because i just had a feeling that once that news hit tumblr, it was going to go every which way because it’s a very misunderstood and heavily sensationalized science.

sources: the epa’s official website, bipm’s website - every link on the wiki pages is legit, too - my own experience in learning about radioactivity from my paternal grandfather who had his doctorate in nuclear science and my old chemistry textbook.

[giovannigiorgio666]

I would like to start using KM/migos as a measurement of speed. How far you get in the time it takes 1 migos album to play.

Example: yesterday I walked at a pace of 4km/1 Migos. That was kinda fast, that means I can walk 60km in 15 Migos albums! Of course I’d have to replay a couple but that’s fine.

I think this unit of measurement is easy to understand and all countries should adopt this as the standard.

Im modifying my car soon to reflect this change.

[ceruleanwhore]

I’ve seen people talking about how the metric system is overall really good except that they wish there were feet in the units of length because it’s a massive jump from centimeters to meters, so I want to remind everyone that decimeters exist. That’s the brilliance of the metric system, that everything is in multiples of ten, so there never actually is just a jump from 1 to 100 like people think there is.