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17:52 but... Isn't that just square root nanometers? I am curious if there is an interpretation of this

Randall Munroe is the guy who makes xkcd, right?

Except it’s metres of travel per cubic metres of fuel so there’s a second unit in there

kWh makes plenty of sense for electrical engineering...Not cursed.

nm x ( nm ^1/2) ^ -1

kWh makes a lot of sense for what it's used for. It's to make it obvious to people who don't know or care about the relationships between different electrical units how much money it will cost to run a thing for a given length of time, by separating the two factors - power and time - for them. It's the same reason we don't write fuel efficiency in square meters even though we could.

Dorks talk about the wattage of a lightbulb. I only illuminate my house with 0.08 horsepower lightbulbs.

Correct me if I am wrong: at 30:35 you say that it is easy to see that there cannot be any cycles, degree-4 vertices etc from the combinatorial description, but not so easy from the positive semidefinite description. I think it is very easy. All minors of a positive semidefinite matrix are positive semidefinite. The cos-matrix of, say, a cycle is not positive semidefinite (because it is not a valid diagram). Hence a valid diagram cannot contain a cycle because this would correspond to a minor that is not PSF. Same for all other forbidden substructures. What I am saying is: it is easy to see that valid diagrams are closed under taking subgraphs.

Surface tension is generally measured in millijoules per square meter and I hate it so much. It's not as screwed as anything on this list, but in paperwork, we just call it [value] ST because it's less annoying. In context, everyone who needs know to understands this. (My job requires, long story short, surface tension measurement, and in addition to the cursed units, they're finicky machines to boot with hilariously fragile US$1200 metal plates that actually touch your liquid and need to be cleaned with a blowtorch)

25:48 hey! That's me!

I watched this video a few years ago and now I am watching it again and I don’t regret it

I thought the Rules of thumb were cursed but i think no one can beat pc.m^-20/3

Yeah, my undergrad computer science professor had (as a joke) made an exercise where we should do something (i don't remember what exactly) with different byte sizes. So with for example the standard 8 bit/byte, but also with 5 bit/byte. Which is cursed in so many ways because the definition of a byte is always exactly 8 bit. No more, no less.

I always felt weird with that kWh unit, now I know why

To be fair, kWh would make sense if you think of watts as the product of volts and amperes, this is where we usually use kWh

Great video.

I modeled the melt of ice in a region of Antarctica in 10^3 Gt a^-1 ice per year. That is, thousand gigatons of ice per year. But, a gigaton is 10^6 tons, and tons are just 10^3 kg (not to mentioned kg being the fundamental unit rather than grams...), so I had thousand billion thousand kg of ice per year. That seemed dumb to me, but also completely understandable. A Gt of water is a cubic kilometer of water. Also the main way glacier ice deforms and moves (other than sliding over it's bed) is called dislocation creep. It is described by a law that relates strain to the n-th power of the stress, with n often taken to be 3. This makes the coefficient outside the exponent have some very weird units. At n=3 there is a coefficient with units of Pa^-3 s^-1. But there's no reason to assume that n has an integer value, and it could range anywhere from 1.8 to about 6 continuously, and the coefficient always has to have units of Pa^-n s^-1.

my brain has been fried. bleh

I mean, the 2 astronomical units is easy. An astronomical unit is the distance between the earth and the sun. So if you're at the other end of the sun from where you were last time, you're twice the distance from the earth to the sun than you were last time. Also, the hubble constant is constant across space. So still a constant.

the only cursed unit I can think of is g/kg you measure the amount of water in 1 kg of air with g/kg

Metrology is much more interesting than i thought

Crazy. The craziest I’ve run across is the stress intensity factor used in fracture mechanics, given by units of stress multiplied by root length (eg MPa times root m, or psi times root inch).

nV/(Hz^1/2) is used to measure noise in electronics. Always thought it was silly unit!

Fracture mechanics analysis is in stress (force/length^2) times √length... So: f*l^(-2)*l^(1/2) = f/l^4 Then there's second moment of inertia, which has l^4 Because...numbers...I guess.

Symmetry is hard and classification of it is like trying to imagine how many thoughts does God have

"Schock pro Quadratklafter" (german, comedic) (X * 60) / [hard to tell, because there are, like, four different definitions of a "Klafter", as a measure of length and at least one definition as a measure of Volume] ^2

My favourite is speed expressed as furlongs per fortnight. Not something you see in any text book.

In high school, I had an extra credit questions for the precise speed of light in a vacuum (299,792,458 m/s). I wrote 1 light year / yr. Got my points.

Oh only 10^9 years old....only exp 9😂 even mol is exp 23

This channel is a gift to humanity

Most annoying is converting km/h to m/s without the 5/18 trick

Absement is an interesting quantity, its measured in metre seconds and is defined as simply the first integral of displacement woth respect to time. So yes, its units are metre seconds.

Or maybe, and stay with me, we all decide to use the metric system and not some out dated unit measuring system that couldnt stay consistent for 4000 years.

Absolutely beautiful

I know it's not THAT BAD compared to some of these, but the only really cursed units I have to interact with somewhat regularly is when calculating the stress intensity factor at the tip of a crack, equation K = sigma * sqrt(pi*crack length), so the units are stress × length^1/2

I remember reading a paper measuring the efficiency of airflow deflections by an aerofoil measured in DeltaQ*M^3/m^2 * m/s and I hated it

so... the thing about kwh is, that its only weird when you convert watts to joules. which no one does, instead, watts in Volts and Amps is way more usefull for most. in that case, wh is an absolutly valid unit, just like Amphours Ah

Not the most cursed unit, but the fact that rocket engine efficiency (Specific Impulse) is measured in seconds is pretty cursed to me

Can we get a moment for how brilliant the MUSIC is for the narration????

Furlounghs per Fortnight?

I personally encountered during my master some beautiful Kinetic constant in electro-chemistry expressed as : (A cm−2)(cm2 mol−1)3/2. It is the most cursed units ever seen.

The music was entirely too loud compared to the speaker and totally unnecessary. Near the end of the video, it had become almost unbearable and not worth finishing.

I still attest that wavenumber is dumb measurement, and that cm^-1 is mildly cursed

Is it just a case of, we happen to be 13.7 B yrs into the lifespan of the universe. I.e. we happen to be at the time line of the universe where it's age happens to equal the reciprocal of the Hubble Constant mad ting

Dimensional analysis is the reason i passed physics

The unit of BMI is quite fun as well. Kg/m2... If you time that with g, you get pressure. 👍👍👍

Just wanted to add this one months later: The efficiency of a power plant is measured in BTU/kWh. Your average engineer might say this is 3412, but the numbers for and denominator are different measurements of the same type with different units.

Holy sh*t

My favourite cursed unit is Joseph-Newtons

I have an APES exam soon and the Kwh definitely confused me while studying