2682: Easy Or Hard

Explain xkcd: It's 'cause you're dumb.
Jump to: navigation, search
Easy Or Hard
"Friction-driven static electrification is familiar and fundamental in daily life, industry, and technology, but its basics have long been unknown and have continually perplexed scientists from ancient Greece to the high-tech era. [...] To date, no single theory can satisfactorily explain this mysterious but fundamental phenomenon." --Eui-Cheol Shin et. al. (2022)
Title text: "Friction-driven static electrification is familiar and fundamental in daily life, industry, and technology, but its basics have long been unknown and have continually perplexed scientists from ancient Greece to the high-tech era. [...] To date, no single theory can satisfactorily explain this mysterious but fundamental phenomenon." --Eui-Cheol Shin et. al. (2022)

Explanation[edit]

This comic uses a table to compare the perceived difficulty of various questions with how easily they're answered in real life. Randall has a long history of comics with similar themes, comparing perceptions to reality. In this case, both the perception and the reality are divided into three levels of difficulty, giving a total of nine categories. Accordingly three of the problems listed are effectively as difficult as one would expect, and the remaining six are not. All three of the questions whose answers are "actually pretty easy to find out" relate to the Eiffel Tower, though there's no apparent theme among the other six questions.

It's likely that this comic was at least partially inspired by writing the books How To, What If?, and What If? 2, the latter of which was published just a few weeks before this comic. These books involve answering very elaborate questions from a scientific point of view. This process likely emphasized that some really strange questions are actually relatively easy to answer, while some questions that seem simple continue to confound scientific knowledge. What if? 2 mentions the fact that no one understands why static charges separate.

Question Perceived Difficulty Real Difficulty Explanation
How tall is the Eiffel Tower? Easy Easy The Eiffel Tower was constructed to be the centerpiece of the 1889 World's Fair. At the time of its construction, it was the tallest man-made structure on earth, which meant that its height was widely publicized since it was first constructed (312m when constructed, and now 330 meters, or 1083 feet, with the antenna added later on). This number is widely published, and easily confirmed with trigonometry.
  • albeit with a ±6 inch differential depending on local air temperature; as the Eiffel Tower is built out of cast steel, it expands according to how much heat builds up in the metal, which in turn is derived from the intensity and daily duration of the Sun's energy. It can also be argued that the number given above is due to rounding, and at sub-millimetrical lengths, the tower's exact height is fluctuating constantly as a result of the aforementioned thermal expansion.
Where was Mars in the sky from Paris on the day the Eiffel Tower opened? Difficult Easy The date of the opening of the tower to the public is well known (May 6, 1889). Since the motions of the planets are predictable, it's clear that calculating the answer should be possible, but it involves enough factors that one might expect it to be very difficult. However, thanks to the existence of online tools, which automatically calculate exactly this sort of thing, finding the answer is quite easy. (It was in the constellation of Taurus, and extremely close to where the Sun also was in the sky during that time so probably not easily directly observable). Alternately, to use the tools available at the time, one might check a nautical almanac for 1889, which gives the position of the major planets (and various other celestial bodies) in the sky throughout the year.
How much does the Eiffel Tower's gravity deflect baseballs in Boston? Near Impossible Easy This problem sounds extremely specific and esoteric, concerning an effect far too small for direct experimentation. But in theory, it's actually a very simple physics problem. Gravitational acceleration is determined entirely by masses and distance, and here even the mass of the baseball can be ignored. Since the mass of the Eiffel Tower and the geographic details of both the tower in Paris and any given location in Boston (perhaps Fenway Park, a famous baseball stadium) are easy to look up, the calculation is quite simple.
How does general anesthesia work? Easy Difficult While biology is always complex, inducing unconsciousness seems relatively simple. In fact, keeping a person unconscious and insensate without causing permanent damage or death is a difficult proposition, requiring a medical specialist. Despite this field being well-established, it might surprise people to know that the mechanism of general anesthesia is still the subject of research, and recent studies have revealed things that we didn't previously understand.
How many ants are there? Difficult Difficult While the existence of ants is a mundane part of life for many people, there are so many of them that coming up with a total number of ants in the whole world sounds exceedingly difficult. It is, in fact, a difficult problem, but experts have done a significant amount of work and have come up with well-founded estimates in the range of 20 quadrillion ants on earth.
What time of year did the Cretaceous impact happen? Near Impossible Difficult The "Cretaceous impact" (the Cretaceous–Paleogene extinction event) happened approximately 66 million years ago. The margins of error on calculating something that ancient are necessarily thousands of years wide at least, so the notion of determining the time of year seems far-fetched. In fact, the problem is a difficult one, but many of the animals killed in the impact were fossilized, and comparing those fossils to modern-day animals at different points in their seasonal growth cycles has led to the suggestion that the impact happened in the northern-hemisphere spring.
Why does your hair get a static charge when you rub it with a balloon? Easy Near Impossible Inducing a static charge by rubbing together two materials is a method that's been known since ancient times. Since human hair has a marked tendency to develop a positive charge, and the latex commonly used in balloons tends to develop a negative charge, rubbing the two together is a very simple way to create an electric field. This process is so simple that it's used for both party tricks and as a fun demonstration of electrical phenomena. Because of this simplicity, most people would assume that the phenomenon is well understood. So it's surprising that the actual mechanism remains an unsolved problem in physics. This also has previously been mentioned in 1867: Physics Confession. The title text quotes a recent paper explaining that, as common as this phenomenon is, there's still no theory that can adequately explain what we observe.
How does Tylenol work? Difficult Near Impossible Tylenol is a brand name for paracetamol, also known as acetaminophen, a drug commonly sold without prescription for pain relief and fever reduction. This drug has been widely used since 1950, and has been well established as being both effective and safe when used properly. Although one would expect the biological mechanism for any drug to be complicated, most people would assume that a drug that's been widely used and studied for so long to be well-documented. Surprisingly, however, the precise action still isn't fully understood. Tufts University
How can relativity be reconciled with quantum mechanics? Near Impossible Near Impossible This remains one of the great unsolved questions in physics. The problem sounds almost unsolvable to laypeople, and remains unsolved even to experts in the field.

Transcript[edit]

Actually pretty easy to find out Very hard, but there have been recent breakthroughs Extremely hard, currently unsolved
Sounds borderline unsolvable How much does the Eiffel Tower's gravity deflect baseballs in Boston? What time of year did the cretaceous impact happen? How can relativity be reconciled with quantum mechanics?
Sounds pretty hard, but you'd assume someone knows Where was Mars in the sky from Paris on the day the Eiffel Tower opened? How many ants are there? How does Tylenol work?
Sounds like it would be easy to look up How tall is the Eiffel Tower? How does general anesthesia work? Why does your hair get a static charge when you rub it with a balloon?


comment.png add a comment! ⋅ comment.png add a topic (use sparingly)! ⋅ Icons-mini-action refresh blue.gif refresh comments!

Discussion

For other people not in US: active ingredient of Tylenol is Paracetamol. -- Hkmaly (talk) 12:51, 7 October 2022 (UTC)

"Now paleontologists have pinpointed during what time of year that millions of years event happened, all thanks to new fossil evidence" (from SciShow) It is probably what's referenced in the "What time of year did the cretaceous impact happen?" Pete Ratchatakul (talk) 13:36, 7 October 2022 (UTC)

Paper cited in the title text: https://www.researchgate.net/publication/360674587_Derivation_of_a_governing_rule_in_triboelectric_charging_and_series_from_thermoelectricity Victor (talk) 13:39, 7 October 2022 (UTC)

AKA https://journals.aps.org/prresearch/pdf/10.1103/PhysRevResearch.4.023131 172.70.210.49 14:17, 7 October 2022 (UTC)

Papers related to the time of the year of the impact:

"... reveal that the impact occurred during boreal Spring/Summer, shortly after the spawning season for fish and most continental taxa." - Seasonal calibration of the end-cretaceous Chicxulub impact event

"Here, by studying fishes that died on the day the Mesozoic era ended, we demonstrate that the impact that caused the Cretaceous–Palaeogene mass extinction took place during boreal spring." - The Mesozoic terminated in boreal spring

Pete Ratchatakul (talk) 13:46, 7 October 2022 (UTC)

Isn't mechanisms of Tylenol well known? https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4912877/

No - that's still a fairly new theory and it isn't fully accepted yet, or confirmed that there isn't anything else going on. It's been an area of controversy for a long time - when I graduated it was still thought it was a cox-3 inhibitor and that wasn't that long ago. (I'm a pharmacist.) 172.70.162.77 12:07, 9 October 2022 (UTC)
I remember reading that the analgesic effect of Tylenol is not significantly greater than placebo, according to some RCTs. So the solution to "how Tylenol works" could simply be that it doesn't. (it's also not that great for treating fever either). USA people are missing out big time for not having approved metamizole/dypirone. 172.71.238.9 22:06, 6 March 2023 (UTC)

I can't vouch for the long-period accuracy of the software that I just used (nor have I cross-checked with any other list or interactive app), but my quick research shows that on 31st March 1889 (dignitaries were officially taken to the top of the Eiffel Tower), Mars was in Pisces, and that in-between then and 6th May (the public got to do the same) it had drifted through Aries (IIRC, forgot to note that explicitly!) and into Taurus, where it was still on 26th May (the lifts opened, and the journey didn't have to be by the stairs!). Although you would have been unlikely to get a good view of Mars as it was quite close to conjunction with the Sun, getting well past Mercury's furthest extent. (In mid-June, it was practically on top of (or over but behind, as it were) the Sun, out of sight for all practical purposes.) I'm sure someone can do a more thorough check than myself, before we set this down properly/succinctly, but it was the first thing I thought of checking for myself. 172.70.90.245 15:56, 7 October 2022 (UTC)

Top right reminds of 2501: Average Familiarity: I guess that for many people relativity and quantum mechanics might fall in the middle right cell, not the top right. 172.69.3.238 16:07, 7 October 2022 (UTC)

I agree. It takes some familiarity with physics to realize that reconciling them is hard. Lay people may not understand these things at all, but they might assume that they're known well enough by scientists that this is at worst a hard problem. Barmar (talk) 16:28, 7 October 2022 (UTC)

Isn't there a category for these types of grids? There should be, he does lots of them. Barmar (talk) 16:28, 7 October 2022 (UTC)

I got 2.125*10^-17 m/s^2, or 3.18*10^-18 N, for the gravitational force/acceleration from the Eiffel Tower on a baseball on Fenway Park. Someone might want to check my calculations, though.--Account (talk) 23:42, 7 October 2022 (UTC)

How did you get those numbers? I was trying to figure it out (for shits and giggles), but I got a different number. What equations/calculations did you use? --72.138.76.186 14:04, 11 October 2022 (UTC)
It occurred to me that the Boston to Paris gravity question might not be quite as easy as it seems, since the relevant distance would be not “as the crow flies,” but more “as the mega-gopher digs.” (I think?) Miamiclay (talk) 21:11, 9 October 2022 (UTC)
I already edited it away from the (implied) suggestion of Great Circle distance (as a trivial understanding of 'distance between', and probably what most searches for a value would turn up). But using latitude, longitude and radius (local, +altitude if you're into the detail) from a sufficiently accurate geophysical model (at least an oblate spheroid) as spherical coordinates leads quickly to true-ish straight-line length. And probably doesn't need to be sigbificantly further adjusted by the small dimple in spacetime that the Earth puts there, or even the fringe distortions of other tide-inducing (and therefore variable) gravitational bodies.
You might even get away with a mere spherical model (and altitude is surely less significant a factor than the difference between that and the spheroid), for a given necessary accuracy level. But I thought that was too much to explain, so left it a bit vaguer. But if further edits are needed, feel free! 172.70.85.49 08:27, 10 October 2022 (UTC)
An oblate spheroid is probably overkill. The difference between the polar and equatorial radii is 20 km, about 0.3% of the radius. Certainly, if you're down to the accuracy where you care about the elevation above sea level, this is going to be important, but otherwise it's not going to change your result much to just use a sphere with the mean radius of the Earth. 172.70.34.213 20:15, 11 October 2022 (UTC)

I can attest to the anesthesia one... Near the beginning of Covid I had to get my foot amputated, something they obviously would knock you out for. However, it was felt that it would be risky in light of Covid so they wouldn't, instead numbing me with a needle to the spine (as I understand it, same idea as the epidural women might get while giving birth). So I was awake and feeling nothing while getting a body part cut off me (both times, I had to get cut twice due to the first cut getting infected). Just shows how delicate even an anesthesiologist's understanding is. NiceGuy1 (talk) 04:03, 8 October 2022 (UTC)

Is it actually a bigger medical mystery how Tylenol works than how general anesthesia works? I figure the latter has had more research dollars spent on it, at the very least. 172.70.178.65 21:17, 10 October 2022 (UTC)

Calculating how much does the Eiffel Tower's gravity deflect baseballs in Boston is easy, but direct observation is insanely hard. Lamty101 (talk) 02:09, 11 October 2022 (UTC)

But just to observe the force, one only needs a torsion balance and some means of entirely relocating the tower to an equidistant point on the Earth's surface but on a plane at right-angles to that of the original vector (for comparative purposes)... ;) 172.70.86.26 08:53, 11 October 2022 (UTC)
I think it might be nitpicky to include in the description, but it's worth noting here that acceleration is a vector, so you'd need to know not just the masses of the two bodies and the distance between them, but also the direction from one to the other. This would affect the direction in which the baseball would be deflected. But if you know the two locations then you already have both distance and direction. Jkshapiro (talk) 08:40, 13 August 2023 (UTC)
Can also likely ignore relativistic effects. Jkshapiro (talk) 08:40, 13 August 2023 (UTC)

Why is the transcript marked as incomplete? 172.70.238.143

Missing title text? New poster/editor didn't know/bother to remove the tag? 108.162.241.51 15:19, 11 October 2022 (UTC)
If it has title text it is overcomplete and TT details would need to be removed from it. Title text is already given verbatim. The Transcript is there to support access to screen-reading/text-searching of information only otherwise available in graphical form, and therefore does not do anything useful by providing the TT (and could be so eadily made to give a different TT). That's my general understanding of the evolved 'policy' on this, anyway. If it changes, I'd suggest that a {{Template}} be inserted below the initially empty Transcript (and above the Discussion insertion) that grabs the {{comic}} field of title text, on the calling page (or optionally another, by numeric parameter, if that would be ever useful) and repeats it verbatim. But, that aside...
If someone has an idea that they have now truly completed the Transcript, they can remove that tag. If someone else believes there are no further worthwhile improvements, they can remove that tag. But someone else might make it 'better', anyway, two minutes or ten years later. And rather than worry about detagging the very latest comic (or even the prior couple, from within the last two) ASAP, I'd personally think about looking at anything untouched for a while from the older comics. And either tweaking (but leaving the tag a little longer for others to review, finishing the job a few days later if no further issues) or finalising as complete rather than polish the turd/gild the lilly.
But I know some people have blitzed all Incomplete tags, and many others clearly consider it not so clear cut and leave them in order to give the benefit of the uncertainty. – Between all our crowd-edits, there seems to be a fairly reasonable concensus, although vanishing Incompletes rarely get replaced by others who disagree but can't themselves (properly) Complete them so it probably biases towards more premature Completing. Which doesn't freeze it, and if the community-accepted 'transcript formatting' hasn't even been done yet it can still be done. (Perhaps the only time I'd reinsert the Incompleteness tag while "finishing" it.) 172.70.86.26 18:09, 11 October 2022 (UTC)

This whole "hair and baloon" thing[edit]

According to a fan theory, hair have a lot of microscopic imperfections like cracks, that tend to rub against things in "microrough" manner.
Meanwhile, ballons, that are made of elastic matter, will have to interact with the hair's ... microscopic stuff.
As a result, there will be quite a surface for interactions on molecular level to bump a lot of molecules one against another without scratching/damaging.
Same thing in lesser proportions happened to me in 2009, when I magnetized my Philips screwdriver by revolving its edges against edges of holer in my PC case.
So, in my opinion, "hair agaist baloon" is a good clue: it takes very little effort unlike revolving a 6mm screwdriver agaist 5 mm holes 162.158.203.40 (talk) Latest revision as of 13:10, 14 October 2022 (please sign your comments with ~~~~)

The big thing about balloon/whatever charge redistribution is (the last I heard) why charges preferentially travel in one direction upon rubbing. Given the complicated mix of surface-molecules, you can't ascribe it to ready-donor/ready-recipient tendencies, such as in an electrolytic cell specifically designed to promote electron/proton exchange from an amorphous mass. And, if nothing else, having been transfered then the force of newly accumulated charge syould want to flow at least as readily in the other direction upon more dynamic contact, so whatever 'incidental' bias from your particular choice of material-pairing (amber/cloth, latex/keratin, or however the charge differential is established in thunderclouds) there's going to quickly be a limit whereupon the charge-per-subunit is hit by diminishing returns (presumably intra-molecular charge distribution 'soaks' some chare distribution away frm the 'skin' of the respective substances).... So it's more complex than just the above, and definitely does need further study, the last I heard. 172.70.91.58 15:07, 14 October 2022 (UTC)
FYI, the effect has a name. It's called triboelectricity (https://en.wikipedia.org/wiki/Triboelectric_effect). 172.70.135.224 00:18, 18 October 2022 (UTC)