2848: Breaker Box

Explain xkcd: It's 'cause you're dumb.
Revision as of 17:49, 31 October 2023 by 172.70.86.8 (talk) (Table of the breakers labels: Added inobtrusive note. (Be careful with colspan and rowspan if modifying!))
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Breaker Box
Any electrician will warn you to first locate and flip the house's CAUSALITY circuit breaker before touching the CIRCUIT BREAKERS one.
Title text: Any electrician will warn you to first locate and flip the house's CAUSALITY circuit breaker before touching the CIRCUIT BREAKERS one.

Explanation

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A Distribution board, referred to as a "breaker box" here and commonly referred to as a "fuse box", "breaker panel", "DB box", and many other names, is a metal box attached to a wall inside a building, usually in some maintenance area, containing several circuit breakers that let power through to various parts of the building. A circuit breaker is an electrical switch, usually in the form of a small lever, that will physically open if too much power is flowing through, as might be the case if a fault occurs, in order to protect appliances.

In most breaker boxes, each individual breaker is labeled to let the operator know what that specific breaker controls. A breaker will usually control something like the outlets or lights in a certain room, or some large appliance.

However, in houses that have been rewired multiple times (or are poorly wired), this can quickly become overcomplicated with seemingly random connections. Randall lives in Boston where much of the housing stock is from the late 1800s or early 1900s, and he is likely to live in a house with non-ideal wiring, which may have inspired this comic.

The comic satirizes these complex wriring setups, with multiple breakers "controlling" arbitrary things, including some that -- in the classic style of XKCD -- may be impossible to hook a breaker up to, getting progressively more absurd to the point of disabling certain laws of physics.

Table of the breakers labels

Label next to breaker Explanation Note
Left column of switches
Kitchen Lights The lights in the kitchen. Standard items
Living room lights The lights in the living room.
Porch lights The lights on the porch.
Bathroom lights and one surprise mystery outlet somewhere The lights in the bathroom, but also a random outlet.

This kind of situation can occur if an electrician – while adding wiring – chooses to wire seemingly logically unrelated things to the same circuit because it's convient/sensible for her to do so. This can mystify future homeowners who don't know the wiring history.

North-facing appliances Difficult, but not theoretically impossible. Presumably this house has (1) a smart wiring system that knows which outlets control which appliances, (2) all appliances with magnetic compasses that report their orientation to the smart home controler, and (3) this breaker is not a simple power on/off but can selectively disable only north-facing appliances.

It is unclear how strict this is as well - it could be as lax as northeast to northwest, or even as strict as north by east to north by west.

Bathtub drain light Bathtubs typically do not have drain lights, but this breaker provides power to that and only that.
Appliances whose names contain the letter "F" Also difficult but not theoretically impossible. Similar to "North-facing appliances," this would require a smart wiring system that can detect the official names of appliances plugged into each outlet, and the ability of this breaker switch to selectively disable certain outlets. (Typical electrical systems do not carry data about names, for starters.)

Some common household appliances that this switch might control: Coffee maker, refrigerator, freezer, fan, air fryer, food processor, waffle iron, fabric steamer, fireplace (electric)

Hot water heater Usually just a heater that creates (and typically stores) hot water. But given the next lebel "regular water heater", this label might actually refer to a water heater that pointlessly heats water that is already hot. This is a joke about the fact that the phrase "hot water heater" is commonly used but is technically redundant (a water heater might be assumed to produce only hot water) or inaccurate (residential water heaters do not heat only water that is already hot). Two "heaters"
Regular water heater The heater for regular water. Together with the switch above, this presumes it's for a heater for heating water that is not yet hot (usually called a "hot water heater", hence the joke).
Outlets in rooms that it's normal to eat pizza in This controls every outlet in rooms that it's normal to eat pizza in, such as the dining room and kitchen and -- depending on the "normal" habits of the inhabitants -- other rooms such as the bedroom, bathroom, or living room (if not already covered by the "living room lights" switch above).
High-pitched hum generator Controls a high-pitched hum generator. This is a call-back to 1590: The Source.
The solution to the cryptogram below: Likely a pun on "breaking" or solving a cryptogram, which is a puzzle where a sentence has been encoded using a cipher, usually simple, and the goal is to determine the cipher and recover the original sentence from the encoded one.

Another explanation is that this switch enables or disables the solution somehow, perhaps controlling its knowability.

Bugs This could either refer to software bugs or actual bugs, both of which do not make much sense to be able to turn off. If this does refer to actual bugs, it may be a reference to 2753: Air Handler.

Though it's unlikely that it's what Randall is referring to, computer bugs switches actually exist. It's a feature in some video game emulators to either run an unofficial patched version or to stay true to the original system, for example to allow bug-exploit speedruns of a video game.

If this switch disables the whole category of bugs (insects, arachnids, and other small arthropods), we'd have no more pests and we'd reduce disease likes malaria and Lyme. Food webs would also collapse, and our world would be overrun with waste.

Right column of switches
A whirring fan you didn't realize was on until now The AC in a building usually creates quiet white noise from fans, which people usually do not hear until they become aware that there is a sound. Other appliances, such as fridges or home servers can have similar effects.
Dishwasher The dishwasher.
Dishes Traditionally, dishes cannot be turned off, as they do not require electricity (excepting for certain light-up, battery-powered novelty plates). "Dishes" could be the label for a dishwasher on another house's breaker box, but this one already used that label. Another, unlikely explanation is that this switch controls 2 or more satellite dishes.
Hallway lights The lights in the hallway or hallways. "Hallway" regions
Hallway outlets The outlets in the hallway or hallways.
Hallway floors This breaker has several potential interpretations:
  1. Outlets in the floors
  2. Electic underfloor heating (heated bathroom floors are a feature in some houses)
  3. Electification of the floors -- not common outside of horror and heist movies.
  4. Disabling all floors entirely, so everything resting on the floors falls through.
Social media This breaker also has several potential interpretations of "turning off social media":
  1. 1 'Digital detoxes', where someone says "I'm going to turn off my social media" and intends to deny themselves access to all their social media apps.
  2. A switch for a parent to turn off all social media entering the house to protect their kids and themselves, which references a type of specialized content filter available through Wi-Fi router settings, not traditionally a breaker box.
  3. A callback to 908: The Cloud. Since most social media platforms are centralized services, it would be theoretically possible to hook up a switch to the main power supply of every server building at once, given some extremely long wires, a breaker capable of handling the abhorrently massive electric load, and agreement from every social media provider(optional).
  4. The theoretical desire by some to "turn off social media" for the world due to its harmful effects on society. As someone who lived before social media and saw its spread over two decades, Randall may be ruing the impacts of social media on civilization and channeling his desire to put the genie back in the bottle.
State law Likely a pun on "State Law Breaker."

Taken literally, it would either disable enforcement of State Law or nullify every single one, creating a state of martial law similar to the premise of the popular movie, "The Purge". It's unclear if this referes to Randall's state of Massachusetts or State Law as a whole concept.

"Legal" items
Federal law Likely a pun on "Federal Law Breaker," though it could also be taken literally, as above. The ramifications of nullifying every US Federal law are immense. Disabling Federal Law while keeping State Law would theoretically fulfull the goals of the "States Rights" advocates, groups of conservatives across US history aiming to return Federal power to the States.
Second law of thermodynamics The Second Law of Thermodynamics, in simple terms, states that the total entropy (or disorder) of an isolated system can only increase over time. It's a fundamental principle that dictates the direction of energy flow, the feasibility of many processes, and provides an arrow of time.

Turning off the second law of thermodynamics would have some pros and cons.

GOOD STUFF
Perpetual Motion Machines: Machines that can do work indefinitely without an energy source would become possible, defying our current understanding of energy conservation.
Reversibility of Processes: Many natural processes that are irreversible under current laws could be reversed. For instance, melted ice could spontaneously turn back into a solid without energy removal.
Recycling Energy: We could theoretically use the same quantum of energy over and over again, leading to ultra-efficient systems and potentially solving many of the world's energy problems.
Reversing Entropy-Driven Processes: Things like mixing cream and coffee or ink in water could spontaneously unmix.

BAD STUFF
End Life as We Know It: All living organisms rely on the second law for crucial processes, including metabolism and reproduction. If the second law were negated, life, at least as we understand it, might not be possible.
No Heat Engines: Engines rely on the flow of heat from hotter to colder bodies. Without the Second Law, our cars, power plants, refrigerators, and many other devices would not function.
Breakdown of Molecular Processes: Molecules spontaneously move from areas of higher to lower concentration due to entropy. Without this, diffusion, osmosis, and many biochemical reactions wouldn't occur as they currently do.
Loss of Directionality: One interpretation of the Second Law provides a directionality to time (the so-called "arrow of time"). Without it, causality and our understanding of past, present, and future could be fundamentally altered.
Unpredictable Outcomes: Turning off the Second Law could result in a universe where outcomes are not probabilistically predictable. You couldn't rely on anything happening as it "should," leading to chaos in every sense.

This law of physics was also explored in the What If? article Fire From Moonlight.

"Physics" items
Friction Friction is the resistive force that opposes the relative motion or tendency of such motion of two surfaces in contact. Turning it off has some upsides and downsides.

UPSIDES
Perpetual Motion Machines: Without friction, once an object starts moving, it would continue indefinitely unless acted upon by another force. This could lead to perpetual motion machines that could generate energy.
Super Efficient Transport: Cars, trains, and other vehicles would glide effortlessly once set into motion, leading to immense energy savings.
Unique Sports: New sports and activities would emerge, where players glide or slide over surfaces without friction.

DOWNSIDES
Walking Would Be Impossible: We rely on friction between our feet and the ground to move. Without it, we would be unable to walk, run, or even stand.
No Manual Dexterity: Holding, grabbing, or manipulating objects would be impossible. Even simple tasks like holding a glass or writing with a pen would be out of reach.
Catastrophic Mechanical Failures: Many machines rely on friction to function. Brakes in cars, for instance, use friction to slow down and stop the vehicle. Without it, uncontrollable accidents would occur.
No Sound: Friction between air molecules creates sound waves. Without friction, the world would be silent.
Breathing Difficulties: Our respiratory system relies on frictional forces when the alveoli in our lungs exchange oxygen and carbon dioxide with the bloodstream.
No Fire: Fire relies on friction for its creation, such as when striking a match. The absence of friction would mean no traditional methods of starting a fire.
Collisions: Objects, once set in motion, would continue to move until they hit something, leading to a myriad of unpredictable and uncontrollable collisions.

Being in a frictionless environment (and a vacuum, as physicists love...) was the subject of 669: Experiment.
Gravity Gravity is a natural force that attracts two bodies toward each other, proportional to their masses and inversely proportional to the square of the distance between their centers.

Turning off gravity would have some advantages and disadvantages.

ADVANTAGES

  • Flight: Without gravity, every leap could turn into a flight. We could push off surfaces and float effortlessly through the air.
  • No Weight Restrictions: Large structures could be built without concern for weight-bearing loads. This would drastically change engineering and architectural designs.
  • New Sports: Zero-gravity sports and activities could become a reality on Earth. Imagine playing basketball or soccer without gravity!

DISADVANTAGES

  • Loss of Atmosphere and Oceans: Without gravity, Earth's atmosphere would dissipate into space, and water from oceans, rivers, and lakes would float away, making life as we know it impossible.
  • Unanchored Chaos: Everything not fixed to the ground, including people, animals, vehicles, trees, and structures, would become airborne, causing massive destruction and chaos.
  • Disruption of Celestial Order: Earth would no longer orbit the Sun, the Moon would drift away, and the structural integrity of the universe, including galaxies and solar systems, would be jeopardized.
Circuit breakers If this was turned off, it would presumably turn off all power in the house since no breaker is supplied or supplying power any more. (Most houses have a main circuit breaker that provides this functionality.)

However, if this circuit breaker disables all circuit breakers everywhere, it would result in Global Infrastructure Collapse, halting essential services, including transportation, healthcare, and communication, and leading to widespread chaos.

Title text
The title text is about causality. Turning off the circuit breaker using the CIRCUIT BREAKER switch may lead to a loop, as the disabled breaker can no longer disable itself, leading to it turning back on, etc. Turning off CAUSALITY first would prevent this loop as causes would no longer have effects.
  • This might be a one way street: turning the CAUSALITY switch from OFF back to ON would be unlikely to do anything if the separation of cause and effect takes precedence over the current switch setting.
A further "Physics" item

Transcript

Ambox notice.png This transcript is incomplete. Please help editing it! Thanks.
[An open breaker box is shown. There are 26 labelled breakers, all of which are on, paired back to back in thirteen rows as a label, switch, switch and label.]
Kitchen lights / A whirring fan you didn't realize was on until now
Living room lights / Dishwasher
Porch lights / Dishes
Bathroom lights and one surprise mystery outlet somewhere / Hallway lights
North-facing appliances / Hallway outlets
Bathtub drain light / Hallway floors
Appliances whose names contain the letter "F" / Social media
Hot water heater / State law
Regular water heater / Federal law
Outlets in rooms that it's normal to eat pizza in / Second law of thermodynamics
High-pitched hum generator / Friction
[There are words that are too small to read on the left breaker's label.]
The solution to the cryptogram below: / Gravity
Bugs / Circuit breakers


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Discussion

added transcript and got to change the name of the thing that created the explanation incomplete tag WOHOOOOoO Me[citation needed] 02:25, 31 October 2023 (UTC)

can't help but notice the 1590 reference someone, i guess(talk i guess|le edit list) 02:43, 31 October 2023 (UTC)

Added explanation! Simple, but it'll do. How do I sign? 172.69.34.159 03:42, 31 October 2023 (UTC)

four tildes (~~~~) someone, i guess(talk i guess|le edit list) 03:08, 31 October 2023 (UTC)
Thanks. I thought that I had tried it earlier and it hadn't worked, but I guess I was wrong. 172.69.34.160 03:46, 31 October 2023 (UTC)

Just added headers, but not good enough with this stuff to add descriptions. go nuts someone, i guess(talk i guess|le edit list) 02:52, 31 October 2023 (UTC)

Got a good laugh out of this one. Does anyone have a guess as to whether the "bugs" at the bottom of the second column refers to computer bugs or insects? Also, some self-referential humor going on at the end there. I guess the breaker box which contains all breakers would indeed contain itself. Jrfarah (talk) 04:31, 31 October 2023 (UTC)

I thought it was some sort of reference to 2753 someone, i guess(talk i guess|le edit list) 04:58, 31 October 2023 (UTC)
It turns off the bunny. 172.69.194.194 11:27, 31 October 2023 (UTC)
Computer bugs switches actually exist. It's a feature in some emulators to either run an unofficial patched version or to stay true to the original system, for example to allow bug-exploit speedruns. Shirluban 172.71.130.70 13:34, 31 October 2023 (UTC)

So... discussion about "Hot Water Heater" vs. "Regular Water Heater"... I was assuming this was a joke regarding the redundancy of the term "Hot Water Heater" since "Water Heater" is already making the water hot, so why would you need to heat water that's already hot? Similar to RAS Syndrome, I thought Randall was making fun of that, but the explanation has a different idea... which... kind of makes sense? But... I've never seen anything like what is being described. Admiral Memo (talk) 05:22, 31 October 2023 (UTC)

After reading "Regular Water Heater", I assumed it was implying that the "Hot Water Heater" was somehow more physically attractive and thus "hotter". --Galeindfal (talk) 14:41, 31 October 2023 (UTC)

Regarding the "one surprise mystery outlet", I don't think it's necessary to assume it was wired that way by mistake. When extending the wiring in an existing house, it's not always easy to wire up an extra breaker, or use the most logically labelled one, and there may not be a compelling safety reason to do so. For instance, in my parents house, the original sockets are all wired from the floor, and when an extra one was needed for a boiler control, it was easier to run a conduit down from the floor above; so that particular socket is on the ring marked "Upstairs Sockets" on the consumer unit. - IMSoP (talk) 09:18, 31 October 2023 (UTC)

I read the "state/federal law" switches as required by said laws. i.e. respective building codes require a "foo switch" always to be installed, whether or not a foo is required, reasonable or even practicable. The switches may be left unlinked to anything that is serviced, or run to the household outlet/power-switch with the label plastered over it saying "don't use for anything but the quarter-inch hoojamaflip grinder" (or whatever it is, in the same sort of manner as "Refrigerator, do not unplug/turn off!" in a communal kitchen.... 141.101.99.166 10:09, 31 October 2023 (UTC)

Some laws contain "circuit breaker" provisions, where some action is triggered when a condition reaches a threshold. Maybe that's what state/federal law refers to. Barmar (talk) 14:25, 31 October 2023 (UTC)
You guys are way too serious. It's a joke, so pick the funniest interpretation possible. Don't try to make it realistic. A circuit breaker turns off the electricity so you can work on the wiring without getting shocked. By analogy, you should be able to use a circuit breaker to turn off the laws when you want to avoid getting fined or arrested. Now that's funny. Rtanenbaum (talk) 12:43, 1 November 2023 (UTC)

...in a separate comment, I have a fuse/switch labelled "Do not turn on!" in my house. It was turned on when I moved in, and (barring actually any reason to mess with anything/’get a man in' for any other purpose) I've left it on. Ditto, for these last six or seven years I've remained ignorant of the purpose of various wall switches (floor-height, one in living room, one at top of stairs, another in a bedroom) that are unlabelled and off (though I have switched them on... no obvious difference to lighting, alarm system, any other system I can imagine they're wired up into and left it pending some future time when I actually have to do something like strip plaster back and discover which (if any?) run of cable leads from/to them. 141.101.99.166 10:11, 31 October 2023 (UTC)

Regarding wall switches that don't have any apparent purpose. Many houses or apartments were not built with lights in the ceiling. So all your lighting came from lamps plugged into wall outlets. They would wire one of the wall outlets to a wall switch, usually near the door. This way you would leave the lamp turned on and use the wall switch to turn it off and on. It takes a little investigation to figure out which wall outlet is being controlled by the switch. Rtanenbaum (talk) 12:43, 1 November 2023 (UTC)
Not applicable, in my case (above 'owner' of the floor switches) because all my sockets(/outlets) in my house have switches on them. One of the mysterious floor switches is indeed very close to a wall-socket, but that wall-socket is a double already with two independent switches (example image). And is of a very similar vintage to the 'mystery switch', by both actual appearance and the how the wallpaper/etc looks. (The house itself is 1930s vintage, but clearly fully updated and rewired to essentially modern standards some time in the last 50 years, and probably far far more recent. No reason for a 'leftover' separate socket switch to have remained/been kept instated.)
The two main possibilities of purpose that I still imagine they controlled are: 1) The burglar alarm, and 2) The storage heater. Originally. Assuming you'd even want multiple different control-switches. But completely bypassed by a later reinstallation. The newer central heating (replacing the storage system) is entirely controlled from a kitchen wall switch, and its own fusebox breaker. And the alarm system has a hallway pad and if it was ever connected to the "Do not turn on" switch (that was actually on), it hasn't suffered at all from the experimental instances of it being turned off (when I thought I'd check).
...it'll all have to wait until I have the next major overhaul, I think. I'll get the next electrician I need (perhaps when replacing the current boiler, or needing more sockets in the workroom) to try and work it out using their usual tricks and tools. 172.70.85.29 15:29, 1 November 2023 (UTC)
LoadingReadyRun did a very funny sketch on a "mystery switch" in their office. [1] Admiral Memo (talk) 03:14, 11 November 2023 (UTC)
In my last house, there was a switch that we couldn't figure out for anything. Finally, we asked the previous owner: they had damaged the wall there during construction, and it was cheaper to put in a dummy switch than to repair the hole! L-Space Traveler (talk) 15:06, 3 December 2023 (UTC)

I believe that the cryptogram may be an attempt to pun on a "code breaker" as a reference to people who solve ciphers. Aberdasher (talk) 13:48, 31 October 2023 (UTC)

Depending on interpretation, "North-facing appliances" could make sense. In my house, I have two main breakers, East and West, each covering (almost) everything in one side of the house. EHusmark (talk) 14:52, 31 October 2023 (UTC)

And, contrary to the "how would the system know?", regarding north-facingness, if you had a ring-main/set of sockets servicing one particular wall (to just one side), there'd be a good chance that anything plugged in there (at least bulky "white goods", even if not smaller things that you might move and turn, like irons and fans) faces away from that particular wall. 172.70.91.236 16:54, 31 October 2023 (UTC)

Definite Borges vibes from the "appliances that face north", "appliances whose names begin with the letter 'F'", "outlets in rooms that it's normal to eat pizza in" section. 172.70.85.50 17:31, 31 October 2023 (UTC)

Amongst other things, there are problems under the "no friction" section. e.g. You might have a perpetual motion machine that would go forever, but without something else (e.g. the anullment of 3LoT) it couldn't also do external work. And of course you can still hold something with zero friction, if you can sufficiently surround, support and/or impale the thing. 172.70.90.230 19:24, 31 October 2023 (UTC)

I agree. Edited. --Hddqsb (talk) 05:01, 1 November 2023 (UTC)

So.... em if you turn off causality, would the switch that turned off causality actually reliably turn off causality, given that causality has been disabled? (added something like this as a note about the title text). (Wowitschris (talk) 19:32, 31 October 2023 (UTC)

Worse than that, if you need to have Causality turned off (for a 'legitimate' reason), there is now no way of preventing anything (including the Causality switch) to be actively toggled. Causaulity could become active again even without any intervention, as well as any number of other effects (of any spontaneous kind whatsoever) for which no cause is now required. 172.69.195.103 19:53, 31 October 2023 (UTC)

"A circuit breaker ...to... protect appliances." --- A pedant would say the breaker protects the wires. When the box is specced and installed, the appliances may not have arrived, and are sure subject to replacement. In both the US and GB Codes the breaker size relates to the wire diameter. If an appliance needs greater protection it should have its own fuse/breaker. Some do, though the trend is to appliances which will fail without flame, smoke, or loud noise.

It's a chicken-and-egg. If you've got a high-current device to install (e.g. electric cooker) then you'll ...hopefully... make sure it has thick copper cables to its outlet, and also sit it behind a fuse/breaker that will take the power throughput. But you still want your breaker to 'break' if something shortcircuity goes on in the cooker. Even/especially if the supply cables are happily feeding the power to it, or its own local fusepoint, because they're not so tightly toleranced that you end up with a long 'heating element' passing through the kitchen wall as well as on your cooker's hobtop (or in its grill/oven compartment(s)).
Overspec the wires, try to tightly spec the current limits on the switches as much as you can anticipate will not ever false-trip. (With the switch from incandescent to LED lighting, many a lighting circuit will now be much further from failure, than designed, but actual ground-faulting will still likely trigger the RCD/whatever.) The aim is to never get so far as a breaking more circuitry than an intrinsic fault has already broken. e.g. motors may burn out, if something jams them, but ideally not spark across to the casing that houses them if they don't suffer direct physical damage. 172.69.195.103 21:29, 31 October 2023 (UTC)

"Bathtub drain light" My bathtub drain is plastic pipe. If the lights are off in the bathroom, but on in the cellar, there's a "light in the drain". No, I don't have a dedicated breaker but that's an idea.....

"Hallway floors" My last house was 1830, so all the electrics were hacked-on. We had a floor outlet in the hall. This used to be more common above a wireable cellar, it avoided snaking the wall. PRR (talk) 20:14, 31 October 2023 (UTC)

Floor outlets are pretty common in large rooms. I mean rooms larger than you'd find a house, say a large classroom. They're used for things like floor polishers or vacuum cleaners, that need to be plugged in near the middle of the space, because the walls are too far away. Also, meeting rooms often have floor jacks under the central table, so people can plug in laptops. Nitpicking (talk) 15:12, 1 November 2023 (UTC)

Wait, what's the joke? I'm pretty sure my (multiple?) circuit boxes are wired exactly like this. 172.71.222.93 (talk) 17:50, 1 November 2023 (please sign your comments with ~~~~)

Would a Fujitsu laptop be turned off by "F" in the name. Sure its a laptop (no f), but perhaps the brand makes its name change. What about if it has an "f" in one language but not another. 172.70.127.158 (talk) 14:03, 2 November 2023 (please sign your comments with ~~~~)

It would depend entirely upon the language/terminology used by the switch-switcher. (Though not what the switch-switcher wants to be the case, e.g. "on this occasion, the 'fridge' is just a 'cooler', but the 'ventillation' is the 'fans'..." 'Cos that'd be silly!) 172.69.194.70 14:31, 2 November 2023 (UTC)

One minor issue: Sound doesn't depend on the friction in air. (minor nerdage alert) The inviscid Euler equations can totally support pressure (acoustic) waves. In fact, without viscosity, they'll damp out somewhat slower, so sound would travel slightly further! 172.70.131.6 00:33, 4 November 2023 (UTC)

I feel like “one niner” and “bad” were overlooked. 172.68.174.233 22:18, 12 November 2023 (UTC)