explain xkcd - User contributions [en]

3097: Bridge Types

2025-06-03T15:37:27Z

162.158.33.225: /* Explanation */

{{comic
| number = 3097
| date = June 2, 2025
| title = Bridge Types
| image = bridge_types_2x.png
| imagesize = 740x581px
| noexpand = true
| titletext = Pontoon bridges are just linear open-sided waterbeds.
}}

==Explanation==
{{incomplete|This page was recently created by a TESSERACT BRIDGE ABUTMENT. Don't remove this notice too soon.}}
This comic shows, in a four-by-four grid of images, a series of bridge types. The first two rows of images are of authentic bridge types, whereas those in the last two rows are progressively more absurd, although real-life examples of some of them exist, as shown in the table below. The joke lies in the progression of bridge types from the simple and straightforward to the complex and ridiculous.

{| class="wikitable"
!Label
!style="width:7em;"|Status
!Type
!Notes
|-
|Plank
|Real
|{{w|Beam bridge}}
|A straightforward piece of solid material (in this case, made of solid wood, but there are {{w|Clapper bridge|other materials}}) is the most basic form of bridge, and generally the easiest to construct, but also the weakest. Consequently, such bridges are only suitable for small spans and light weights (such as a footbridge over a stream).
|-
|Rope
|Real
|{{w|Simple suspension bridge}}
|Rope bridges consist of several lengths of rope anchored on both sides of the span. Typically, one or more ropes will be intended to support the crossing load (possibly with boards or some other walkway between them), and additional ropes will act as handrails, reducing the risk of falling. These are typically only intended for foot traffic, due to their light construction and lack of rigidity. Because of the simple materials and relative ease of construction, they're often used as improvised bridges.
|-
|Truss
|Real
|{{w|Truss bridge}}
|A truss is a common type of framework consisting of supports connected in a series of triangles which provide support for a load. This design provides significant strength and rigidity with minimal material and weight. A truss bridge can either have the truss above the bridge platform (as in the drawing) or underneath it (also known as a deck truss). This is the first bridge type on this list which is commonly used for vehicle traffic.
|-
|Trestle
|Real
|{{w|Trestle bridge}}
|A trestle bridge is held up by supports reaching all the way to the ground beneath. Typically at least some of the supports will slope outward to give a larger base of support. Once common for railroads, these are less popular nowadays, but are still seen in certain areas and applications.
|-
|Arch
|Real
|{{w|Arch bridge}}
|Arches are one of the oldest kinds of bridges for carrying significant loads. They can be made out of rock or metal. Each span consists of an arch resting on supports. Simple arch bridges rest on both sides of a river or other gap, but longer bridges (as in the drawing) will have intermediate pillars to support multiple arches. The arches distribute the load, allowing a relatively small number of pillar to support weight across the entire deck of the bridge.
|-
|Suspended Arch
|Real
|{{w|Tied-arch bridge}}
|Tied arch bridges use a similar concept as arch bridges, but the arch is instead positioned overhead, with the deck supported by suspended cables. Such bridges may use a single arch (as in the drawing) or multiple arches in succession.
|-
|Draw
|Real
|{{w|Drawbridge}}
|Drawbridges are used to allow ships to pass through obstacles like bridges. They use a cable to pull up one or both sides of the bridge to create enough height clearance for vessels to pass through.
|-
|Suspension
|Real
|{{w|Suspension bridge}}
|A suspension bridge suspends its deck with cables or rods from a cable linked to a pillar and a point a certain distance from each pillar
|-
|Filler
|Real method of maintaining {{w|Grade (slope)|grade}}, not really a 'bridge'
|{{w|Embankment (earthworks)|Embankment}}, {{w|Causeway}} or even a {{w|Dam}}
|Serves the purpose of allowing travel across the gap, but by removing (or {{w|Culvert|mostly removing}}) passage through the gap itself. By filling the gap with hard, irregular material (most commonly rocks), support can be provided, while still allowing water to flow through the gaps. Due to the generally small size of the gaps, generally only slow-flowing water can reliably get through.
|-
|Budget Overrun
|Real (with an absurd name)
|{{w|Cable-stayed bridge}}
|Specifically, the pictured bridge is a {{w|cantilever spar cable-stayed bridge}}, similar in appearance to the {{w|Samuel Beckett Bridge}} in Dublin. Many bridges in this category suffer severe cost overruns. Randall may be drawing upon his local knowledge of the {{w|Leonard P. Zakim Bunker Hill Memorial Bridge|Zakim Bridge}} in downtown Boston's {{w|Big Dig}}, also strongly associated with cost overruns.
|-
|Jump
|Not Real
|Similar to a pair of small {{w|cantilever bridge}}s, constructed at an incline.
|A "bridge" that appear to be being used by a skateboarder, though in a manner far more dangerous than any jump in a typical skatepark. While not {{w|London Buses route 78#History|normally}} a feature of the highway, jump ramps can be used for gap-crossing stunts by almost any vehicle with sufficient speed. Partial bridges, which allow ''some'' vehicles using them to safely cross the gap, iconincally featured in {{w|The Dukes of Hazzard}} TV show, as well as common in various {{w|The Man with the Golden Gun (film)#Car stunts|action}} {{w|Speed (1994 film)#Filming|films}}, though typically less easy to use correctly than the setting implies.
|-
|Halfhearted
|Real
|[https://www.archdaily.com/184921/moses-bridge-road-architecten Moses bridge]
|The diagram shows that there was barely any attempt to bridge the gap in the landscape at all, just take the 'deck' down into it and back up out again. The concept may have been inspired, in part, by [https://www.fastcompany.com/90186315/the-strange-art-of-the-melting-bridges-of-google-earth an artifact in Google Earth software].
Bridge exist, at the {{w|Fort de Roovere}} in Halsteren, Netherlands and elsewhere, that resemble this 'solution', though these would have involved much thought and commitment in their building, possibly more 'hearted', even, than any more conventional bridge design, especially in the provision of stairs to allow easier ingress/egress (at least for foot traffic) than in the comic's version.
|-
|Waterbed
|Not a bridge
|{{w|Waterbed}}
|Rather than a bridge, it is more like another version of a causeway (see 'Filler') using trapped water to maintain the upper surface.
Named for a 'mattress' type, which is usually a raised surface ''on top of'' a piece of bedframe, with an unusual approach to padding and comfort.
|-
|L'Engle
|Not real
|[https://www.refinery29.com/en-us/2018/03/192728/tesseract-definition-wrinkle-in-time-space-dimension Tesseract AWIT] not {{w|Tesseract|Tesseract (geometry)}}
|References {{w|A Wrinkle In Time}} by Madeleine L'Engle. Characters cross great distances by "tessering", moving via a tesseract through a higher dimension which essentially brings the two ends of the journey together from the perspective of the traveler. The image shows the two ends of the gap being brought together, with the gap apparently crumpled in between them.
|-
|Fun
|Not real
|
|It is a loop-de-loop, possible allusion to [[2935: Ocean Loop]].
|-
|Repurposed Elevator
|Real, but not as displayed
|Horizontal elevator / {{w|People mover|People mover}}
|There are various implementations of such designs, the best-known one is probably the {{w|Schmid Peoplemover|Schmid Peoplemover}}.
However, unlike a regular people mover, where the door stays upright, the image shows a regular elevator that has been rotated 90 degrees.
|-
|''(Title text)''
|Real
|{{w|Pontoon bridge}}
|Pontoon bridges are described as a series of fictitious "waterbed bridges", as shown above, but constructed without sides. This would mean that that the 'bed'-supporting water flows in one side and out the other, if there is any passage or tidal flow of water. It may technically mean that you cannot cross {{w|The Same River Twice|the same bridge twice}}.
Pontoons rely upon buoyancy, either of the whole deck or distinct floating elements, whereas an enclosed "waterbed" bridge would rely upon the strength of the membrane to keep the mass of water within it, and thus the deck above that mass.
|}

==Transcript==
{{incomplete transcript|Don't remove this notice too soon.}}
:Bridge Types

:[A 4x4 matrix of 16 ways to cross the same rectangular hole in the ground]

:Plank [shows a plank laid over the hole]

:Rope [shows a rope bridge with rope guardrail]

:Truss [shows a truss bridge with a triangular truss above the bridge deck]

:Trestle [shows a trestle bridge]

:Arch [shows stone arches supporting a straight deck]

:Suspended Arch [shows a single arch, with the bridge deck suspended from it]

:Draw [shows a truss bridge, with one half opened like an unrealistic draw bridge]

:Suspension [shows the bridge deck suspended from a cable strung between two pillars and the shores]

:Filler [shows the hole filled with dirt and stones]

:Budget Overrun [shows a bridge deck suspended by cables from an artistically shaped pillar]

:Jump [shows two ramps at the edges of the hole, and a skateboarder jumping across the hole]

:Halfhearted [shows a ramp at each side of the hole that leads down to the bottom]

:Waterbed [shows the hole filled with water, two fish and an octopus, a wobbly covering, and two stick figures crossing]

:L'Engle [shows the hole warped such that the opposite shores meet]

:Fun [shows a loop-de-loop rollercoaster bridging the hole, and a skateboarder using it to get across]

:Repurposed Elevator [shows an elevator tower, rotated sideways as a whole, laid across the hole. 2 stick figures using the elevator are also rotated.]

{{comic discussion}}<noinclude>

[[Category:Engineering]]
[[Category:Comics featuring Cueball]]
[[Category:Multiple Cueballs]]
[[Category:Animals]]

3090: Sail Physics

2025-05-17T20:10:06Z

162.158.33.225: /* Explanation */ Tacking isn't a mechanism. It's something you have to do to exploit the actual effects. I plan to reinsert a later reference to it, to that effect, after some other edits.

{{comic
| number = 3090
| date = May 16, 2025
| title = Sail Physics
| image = sail_physics_2x.png
| imagesize = 699x263px
| noexpand = true
| titletext = Turning in other directions can be accomplished by using a magnetized centerboard and ocean currents, since a current flowing through a magnetic field induces a Laplace force.
}}

==Explanation==
{{incomplete|This page was created by a wind-blown electron. Don't remove this notice too soon.}}

This comic starts off looking like a straightforward explanation of how sailboats can travel upwind — a topic that continues to spark debate and refinement in physics circles. However, it quickly veers into a completely fictional and incorrect theory involving triboelectric charging and the Lorentz force, rather than referencing real mechanisms like {{w|airfoil|aerodynamic lift}}.

This humor works at another level — most interaction of physical things at macro scale (humans and boat sized objects) are electromagnetic in nature. So one unaware of sailing mechanics may start to explain the situation with electromagnetism, and could come to this line of thinking, but it is wrong. If we are to consider this, we find that either no force is appearing in the direction shown, or very little.

{{w|Triboelectric effect|Triboelectric effect}} is acquisition of static charge by friction between two objects, which in turn depends on effective interaction surface area. But the charge acquired would be very small, and not be comparative to gravity by orders of magnitudes (gravity is a weaker force, but involves a whole planet's-worth of mass normally dominating the static-effects of all but the lightest particles/hairs/scraps of tissue, or significantly buoyant toy balloons). There is more charge generated due to the running of the boat through water, in a realistic situation. Following on from the initial assumption, however, the comic assumes motion in a downstream direction, effectively due to normal forces on the sail. Further, the comic applies this motion as of that of a charged object in Earth's magnetic field. If we are to consider this magnetic field to be roughly parallel to Earth's surface, which would be true for situations close to the equator (as Earth's magnetic field is effectively that of dipole bar magnet, which is roughly aligned with our planetary rotational axis). The net Lorentz force on the boat would be F = qvB, and since both velocity of both and magnetic field lines are in the same plane (as viewed in the above sketches, in a top-down manner), then the force would be perpendicular to the plane. That is, along the direction of gravity for the boat, which will not cause any motion in plane. If we consider magnetic field lines to be perpendicular to Earth's surface (close to poles), even then the magnitude of the force is very small. If we consider a net charge of 1 coulomb across the boat (which is an extremely high amount of charge, at which point, the charge would try to accumulate on sharp objects, and due to this high charge density, either charge will leave the boat through coronal discharge, or the sharp objects would start to break from the boat (this is due to high self electrostatic energy, which is roughly proportional to square of charge density divided by radius of curvature of object, if the bonding between object is not strong enough, then this electrostatic energy can overcome this bonding energy), assuming that this charge does not cause the ship to break or the charge to leak out to water body, as the charge would like to spread to minimise the electrostatic energy), and if we consider field strength of order 0.0001 Tesla (close to typical values on surface), and take wind speeds of 10000 m/s (also very high) then the net force on ship would be 1 N, which for a boat of mass 10 kg (less for a typical boat, but is appropriate for a makeshift raft) cause a net acceleration of 0.1 m/s^2. Which is not tiny, but due to friction across the boat, would be cancelled out (by 1 or 2 orders of magnitude). This is considering the best possible case. For more reasonable charge values, this force would be about a trillion times weaker, and hence this will not cause any practical motion.{{citation needed}}

If the described effect were actually significant, it wouldn't always make boats turn upwind. A positively charged boat would turn counter-clockwise on the northern hemisphere, where the magnetic field points down, and clockwise on the southern hemisphere, where the magnetic field points up. Thus it would turn upwind or downwind depending on which side of the boat faces the wind. A negatively charged boat would turn in the opposite direction. To beat to windward it would be necessary to switch between two sails made of different materials – one sail to accumulate a positive charge, and another to accumulate a negative charge.

==Transcript==
{{incomplete transcript|Don't remove this notice too soon.}}

[Panel 1]

How sailboats use physics to sail upwind:

[A schematic boat with a sail is shown (top-down view). Winds shown with directional arrows, pointing in the direction of the sail (going towards 4:30 on a clock face).]

[Panel 2]

1. Wind passing over the sail strips away electrons via the triboelectric effect.

[Schematic similar to panel 1, but with charged ions shown across both sides of the sail, representing the triboelectric effect.]

[Panel 3]

2. The positively charged boat is blown downwind; its movement in Earth's magnetic field produces a Lorentz force.

[The same schematic, except a force vector is shown in the direction of the wind, and a perpendicular force vector (along 1:30 on a clock face) is shown with a dashed arrow.]

[Panel 4]

3. The Lorentz force acts perpendicular to the direction of motion, redirecting the boat upwind.

[A net force vector is shown perpendicular to the downstream vector.]

{{comic discussion}}<noinclude>

3001: Temperature Scales

2024-10-25T20:33:58Z

162.158.33.225: /* Trivia */ Undoing remnant accidentally left due to having to solve a mysterious Edit Conflict...

{{comic
| number = 3001
| date = October 21, 2024
| title = Temperature Scales
| image = temperature_scales_2x.png
| imagesize = 740x535px
| noexpand = true
| titletext = In my new scale, °X, 0 is Earths' record lowest surface temperature, 50 is the global average, and 100 is the record highest, with a linear scale between each point and adjustment every year as needed.
}}

==Explanation==

Since the invention of the {{w|thermometer}}, a number of different {{w|temperature}} scales have been proposed. In modern times, most of the world uses the 1742 {{w|Celsius}} scale for everyday temperature measurements. A small number of countries (the USA and {{w|Territories of the United States|its territories}}, the Bahamas, Belize, the Cayman Islands, Liberia, and Palau) retain the {{w|Imperial units|imperial system}} (or the related {{w|United States customary units|US customary system}}), which uses the 1724 {{w|Fahrenheit}} scale. The other widely used temperature scale is the 1848 {{w|kelvin}}, which uses the same scale as degrees Celsius, but is rooted at {{w|absolute zero}}, making it both useful in scientific calculations and easy to convert to and from °Celsius (which, along with °Fahrenheit, is now officially defined relative to kelvin). The Kelvin scale has been part of the widely adopted official {{w|metric system}} since 1954. Even in countries that use Fahrenheit, scientific measurements are usually made in degrees Celsius or kelvin.

The comic compares these scales, and a number of others, on [[Randall]]'s scale of "cursedness." The joke is highlighting how different the temperature scales are, and how impractical most of them are. All of the listed scales are real, but may be considered obsolete to varying degrees. Please see also [[1923: Felsius]], a combination of degrees Fahrenheit and Celsius.

{| class=wikitable
! scope="col" | Unit
! scope="col" | Water freezes
! scope="col" | Water boils
! scope="col" | Notes
! scope="col" | Cursedness
! scope="col" | Explanation
|-
| {{w|Celsius}} || 0 || 100 || Used in most of the world || 2/10 || The Celsius (°C) scale, also known as "centigrade", was devised by Swedish astronomer {{w|Anders Celsius}} in 1742 and revised in 1745, a year after his death. 0°C represents the freezing point of water and 100°C represents the boiling point, both under {{w|standard atmospheric pressure}}. The Celsius scale is now defined in terms of kelvin. By the given "cursedness," it is regarded as one of the least problematic temperature scales.
|-
| {{w|Kelvin}} || 273.15 || 373.15 || 0K is absolute zero || 2/10 || Kelvin (plural with a lowercase 'k' as a temperature unit; or as the symbol 'K', without the degrees symbol '°', unlike most other such units) is a unit of temperature devised by {{w|Lord Kelvin}} in 1848. It uses the same scale as Celsius but is shifted by 273.15 to set absolute zero at 0K (based on the {{w|Boltzmann constant}}.)
<center>Celsius = kelvin - 273.15</center>
<center>kelvin = Celsius + 273.15</center>
While kelvin is very useful for calculations in {{w|thermodynamics}} and material physics, it can be unintuitive to laypersons.
|-
| {{w|Fahrenheit}} || 32 || 212 || Outdoors in most places is between 0–100 || 3/10 || Fahrenheit (°F) is officially used in a few countries and informally in several others. It originated in a time when factors of 360 were favored in science over powers of ten, which is why the freezing and boiling points of water are set 180° apart. Devised around 1724, {{w|Daniel Fahrenheit}} chose not to base 0° on the freezing point of water, instead originally setting it at the coldest temperature he could achieve: the freezing point of an {{w|ammonium chloride}} {{w|brine}} solution.
<center>Celsius = (Fahrenheit - 32) × 5/9</center>
<center>Fahrenheit = Celsius × 9/5 + 32</center>
Although those reference points are now considered arbitrary and outdated by modern scholars, the scale gained popularity in Anglophone countries, possibly because everyday weather conditions usually fall handily all across the range 0–100°F, and 100°F is {{w|Human body temperature#Historical understanding|coincidentally close to normal human body temperature}}. The Fahrenheit scale remains officially used only in Randall's home country (the U.S., and its territories), the Bahamas, Belize, the Cayman Islands, Liberia and Palau.
|-
| {{w|Réaumur scale|Réaumur}} || 0 || 80 || Like Celsius, but with 80 instead of 100 || 3/8 || Abbreviated as °Ré, this system devised by {{w|René Antoine Ferchault de Réaumur}} in 1730 was used in some places until the early 20th century, mostly for cheese-making.
<center>Celsius = Réaumur / 0.8</center>
<center>Réaumur = Celsius × 0.8</center>
The rating (3/8) is a joke on the boiling point of water in this system being 80 instead of 100 as it is in Celsius; converting this to an out-of-ten scale would give 3.75/10, labeling it as more cursed than Fahrenheit but less so than Rømer.
|-
| {{w|Rømer scale|Rømer}} || 7.5 || 60 || Fahrenheit precursor with similarly random design || 4/10 || Abbreviated as °Rø, this scale was created by the Danish astronomer {{w|Ole Rømer}} around 1702. Much like Fahrenheit, it originally used the freezing point of ammonium chloride brine as the benchmark for 0°, and the scale is built with factors of 360 in mind with the boiling point of pure water at 60°. Like the Fahrenheit scale, the freezing point of pure water was not originally considered significant by Rømer, but the scale was later updated to give the value of 7.5 at this point.
<center>Celsius = (Rømer - 7.5) × 40/21</center>
<center>Rømer = Celsius × 21/40 + 7.5</center>
The Rømer scale is considered the predecessor of both the Celsius and Fahrenheit scales, because Réaumur was inspired by Rømer's scale, Celsius based his work on Réaumur and Fahrenheit specifically designed his scale with more divisions than Rømer's to reduce the necessity for fractions.
|-
| {{w|Rankine scale|Rankine}} || 491.7 || 671.7 || Fahrenheit, but with 0°F [''sic;'' should be 0°Ra] set to absolute zero || 6/10 || The Rankine scale (°R or °Ra), devised in 1859 by {{w|William Rankine}}, is to Fahrenheit what kelvin is to Celsius, an absolute raher than a relative scale. The scale is mostly obsolete, but is still occasionally used in legacy industrial operations where absolute temperature scales are required. It is described as more cursed than the otherwise identical Fahrenheit scale, despite being rooted at a more universal zero point.
<center>Celsius = (Rankine - 491.67) × 5/9</center>
<center>Rankine = (Celsius + 273.15) × 9/5</center>
Another comic, [[2292: Thermometer]], expresses disdain for this scale.
|-
| {{w|Newton scale|Newton}} || 0 || 33-ish || Poorly defined, with reference points like "the hottest water you can hold your hand in" || 7-ish/10 || The famous scientist and mathematician {{w|Isaac Newton}} published this scale in 1701, which was referred to by the the °N symbol. Sadly, the degrees of temperature specified do not correlate exactly with amounts of {{w|heat}}. The cursedness rating (7-ish/10) is a joke about the vagueness of the scale's definition.
<center>Celsius = Newton × 100/33</center>
<center>Newton = Celsius × 33/100</center>
Very few scientists other than Newton ever used this scale,{{Actual citation needed}} but it did appear on commercial thermometers around 1758.<ref>https://www.scienceandsociety.co.uk/results.asp?image=10413117&wwwflag=&imagepos=43</ref>
|-
| {{w|Wedgwood scale|Wedgwood}} || –8 || –6.7 || Intended for comparing the melting points of metals, all of which it was very wrong about || 9/10 || Created by the potter {{w|Josiah Wedgwood}} in 1782, the '°W' scale was based on the shrinking of clay when heated above red heat, but was found to be very inconsistent.
<center>Celsius = (Wedgwood + 8) × 100/1.3</center>
<center>Wedgwood = (Celsius × 1.3/100) - 8</center>
The comic has a typo, as the scale is called Wedgwood, without the second 'e'.
|-
| Galen || –4? || 4?? || Runs from –4 (cold) to 4 (hot). 0 is "normal"(?) || 4/–4 || The Greek physician {{w|Galen}} suggested a "neutral" temperature around 180 A.D.,<ref>https://www.loebclassics.com/view/galen-temperaments/2020/pb_LCL546.3.xml</ref> when he was a prominent physician in the {{w|Roman Empire}}. Created by mixing equal parts of boiling water and ice, on either side of this neutral point he described four degrees of heat and four degrees of cold.
<center>Celsius = (Galen × 100 / 8) + 22</center>
<center>Galen = ((Celsius - 22) / 100) × 8</center>
This range from +4 to –4 is humorously used as its rating, implying -100% cursedness. Technically this makes it the least cursed of all the listed scales, but the idea of negative cursedness (or cursedness itself) would be Randall's invention. There is no standard modern abbreviation for Galen's scale.
|-
| {{w|Celsius#History|''Real'' Celsius}} || 100 || 0 || In Anders Celsius's original 1742 specification, bigger numbers are ''colder''; others later flipped it || 10/0 || Most scales' temperatures can be indefinitely large, but have an absolute minimum temperature. By starting at a maximum value and counting down, this scale is indeed cursed, as nearly all possible temperatures (possibly to the equivalent of 1.42x1032K, considered [https://doi.org/10.4236/jamp.2024.1210198 the maximum attainable physical temperature]) will be negative in this implementation. The cursedness rating (10/0) is a joke on the scale "flipping" the fixed points of modern Celsius. Division by zero is strictly undefined (see [[2295: Garbage Math]]) and may be interpreted in a number of counter-intuitive ways.
<center>Celsius = 100 - real_Celsius</center>
<center>real_Celsius = 100 - Celsius</center>
The original logic was that zero could be easily calibrated to the height of a {{w|Millimetre of mercury|column of mercury}} at the temperature of boiling water, and further measurements then made of the amount it ''reduced'' in height under cooler conditions. This orientation survives in the historic {{w|Delisle scale}} devised in 1732 by French astronomer {{w|Joseph-Nicolas Delisle}}, which arguably inspired the Celsius scale. The scale originally used by Professor Celsius was changed, to more or less the form already described above, after his death in 1745. Delisle's scale was never reversed.
|-
| [https://physics.stackexchange.com/questions/459851/john-daltons-temperature-scale#459863 Dalton] || 0 || 100 || A nonlinear scale; 0°C and 100°C are 0 and 100 Dalton, but 50°C is 53.9 Dalton || 53.9/50 || {{w|John Dalton}} proposed a logarithmic temperature scale in 1802 during his work on what became {{w|Charles's Law}}. The scale is defined so that absolute zero is at negative infinity, with the exponent chosen to match Celsius at 0 and 100:
<center>Celsius = 273.15 × ''e''(Dalton / 320.55) - 273.15</center>
<center>Dalton = 320.55 × {{w|Natural logarithm|''ln''(}} (Celsius + 273.15) / 273.15 )</center>
There is no standard abbreviation for Dalton's scale. While Dalton temperature is defined for all positive and negative numbers, the nonlinear scale is difficult to work with since the amount of heat represented by a change of one degree Dalton is not constant. Degrees Dalton differs from Celsius by as much as 3.9 degrees between 0 and 100, but diverges much more for more extreme temperatures. The rating (53.9/50) is a joke about the unit, as 53.9 Dalton equates to 50 degrees Celsius — i.e., it could be said to be 107.8% (even more than entirely) cursed.
|-
| °X || 42.9 || 151.4 || '''Title text:''' "In my new scale, °X, 0 is Earths' [''sic''] record lowest surface temperature, 50 is the global average, and 100 is the record highest, with a linear scale between each point and adjustment every year as needed." || Randall has not stated the cursedness of his new scale || The {{w|Lowest temperature recorded on Earth|record lowest surface temperature on Earth}} as of 2024 is –89.2°C (–128.6°F), recorded at the {{w|Vostok Station|Vostok Research Station}} in Antarctica on July 21, 1983.<ref>https://wmo.asu.edu/content/world-lowest-temperature</ref> The average surface temperature as of 2023, the most recent available, is 14.8°C (58.6°F.)<ref>https://climate.copernicus.eu/climate-indicators/temperature</ref> The {{w|Highest temperature recorded on Earth|record highest temperature}} is 56.7°C (134.1°F), recorded on July 10, 1913 at {{w|Furnace Creek, California|Furnace Creek Ranch}} in Death Valley, California.<ref>https://wmo.asu.edu/content/world-highest-temperature</ref>

"Surface" temperatures are measured at 1.5 meters above ground inside a shaded shelter, to accurately represent the temperature of the air, because temperatures closer to the ground are often quite different due to effect of absorbing sunlight (or a lack thereof, e.g. at night or under clouds), and the thermal capacity of soil.

{{cot|Derivation and graph}}
To break the scale into two linear parts (below and above 14.8°C), we define two separate equations for each range:

1. Below 14.8°C (from –89.2°C to 14.8°C):
* 0 °X corresponds to –89.2°C
* 50 °X corresponds to 14.8°C

We calculate the slope m₁:

<center>m₁ = (50 – 0) / (14.8 – (–89.2)) = 50 / (14.8 + 89.2) = 50 / 104 ≈ 0.48</center>

Now, using the point (14.8°C, 50 °X), we calculate the intercept b₁:

<center>50 = 0.48 × 14.8 + b₁</center>

<center>50 = 7.1 + b₁</center>

<center>b₁ = 50 – 7.1 = 42.9</center>

Thus, the equation for temperatures '''below 14.8°C''' is:

<center>'''X = 0.48 × C + 42.9'''</center>

2. Above 14.8°C (from 14.8°C to 56.7°C):
* 50 °X corresponds to 14.8°C
* 100 °X corresponds to 56.7°C

We calculate the slope m₂:

<center>m₂ = (100 – 50) / (56.7 – 14.8) = 50 / 41.9 ≈ 1.19</center>

Now, using the point (14.8°C, 50 °X), we calculate the intercept b₂:

<center>50 = 1.19 × 14.8 + b₂</center>

<center>50 = 17.6 + b₂</center>

<center>b₂ = 50 – 17.6 = 32.4</center>

Thus, the equation for temperatures '''above 14.8°C''' is:

<center>'''X = 1.19 × C + 32.4'''</center>

;Freezing and boiling points of water

Freezing point of water (0°C): Since 0°C is below 14.8°C, we use the equation X = 0.48 × C + 42.9:

<center>X = 0.48 × 0 + 42.9 = 42.9</center>

So, '''the freezing point is 42.9 °X.'''

Boiling point of water (100°C): Since 100°C is above 14.8°C, we use the equation X = 1.19 × C + 32.4:

<center>X = 1.19 × 100 + 32.4 = 119 + 32.4 = 151.4</center>

So, '''the boiling point is 151.4 °X.'''

[[File:XvsC.png|400px|center]]

See also [[2701: Change in Slope]] for a general discussion of separate linear scales between three points.
{{cob}}
Due to high temperature records increasing almost every year (and similarly the trend in average temperatures) as a result of {{w|climate change}}, Randall's new °X scale must be re-calibrated each year. While the subsequent °X value being given to everyday benchmark temperatures will vary over time, more extreme values like absolute zero or the {{w|Tungsten#Physical properties|melting point of tungsten}} will shift vastly more.
|}

==Trivia==

In the various scales, this is a table of several benchmark temperatures.

;[Warning, not proofread.]

{| class=wikitable style="text-align: center;"
! Unit scale
! Sample {{w|room temperature}}
! {{w|Properties of water#Melting point|Freezing point of water}}
! {{w|Boiling point#Boiling point of water with elevation|Boiling point of water}} 
! {{w|Human body temperature}} (midpoint)
! Recommended {{w|Refrigerator#Temperature zones and ratings|refrigerator temperature}} 
! Recommended {{w|Refrigerator#Freezer|freezer temperature}} 
! "Warm bath" temperature 
! "{{w|Coffee#Brewing|Hot coffee}}" temperature 
|-
| Celsius || 22 °C || 0 °C || 100 °C || 37 °C || 2.5 °C || -18 °C || 39 °C || 77 °C
|-
| Kelvin || 295 K || 273 K || 373 K || 310 K || 276 K || 255 K || 312 K || 350 K
|-
| Fahrenheit || 72 °F || 32 °F || 212 °F || 98.6 °F || 36.5 °F || -0.4 °F || 102 °F || 171 °F
|-
| Réaumur || 17.6 °Ré || 0 °Ré || 80 °Ré || 29.6 °Ré || 2 °Ré || -14.4 °Ré || 31.2 °Ré || 61.6 °Ré
|-
| Rømer || 19.1 °Rø || 7.5 °Rø || 60 °Rø || 26.9 °Rø || 8.8 °Rø || -2 °Rø || 28 °Rø || 47.9 °Rø
|-
| Rankine || 531 °Ra || 492 °Ra || 672 °Ra || 558 °Ra || 496 °Ra || 459 °Ra || 562 °Ra || 630 °Ra
|-
| Newton || 7.3 °N || 0 °N || 33 °N || 12.2 °N || 0.8 °N || -5.9 °N || 12.9 °N || 25.4 °N
|-
| Wedgwood || -7.71 °W || -8.00 °W || -6.70 °W || -7.52 °W || -7.97 °W || -8.23 °W || -7.49 °W || -7.00 °W
|-
| Galen || 0 || -1.76 || 6.24 || 1.20 || -1.56 || -3.20 || 1.36 || 4.40
|-
| ''Real'' Celsius || 78 || 100 || 0 || 63 || 98 || 118 || 61 || 23
|-
| Dalton || 24.8 || 0 || 100 || 40.7 || 2.9 || -21.9 || 42.8 || 79.6
|-
| °X || 59 °X || 43 °X || 151 °X || 76.4 °X || 44.1 °X || 34.3 °X || 78.8 °X || 124 °X
|}

==Transcript==

:Temperature Scales

:[A table with five columns, labelled: Unit, water freezing point, water boiling point, notes, cursedness. There are eleven rows below the labels.]

:[Row 1:] Celsius, 0, 100, Used in most of the world, 2/10
:[Row 2:] Kelvin, 273.15, 373.15, 0K is absolute zero, 2/10
:[Row 3:] Fahrenheit, 32, 212, Outdoors in most places is between 0–100, 3/10
:[Row 4:] Réaumur, 0, 80, Like Celsius, but with 80 instead of 100, 3/8
:[Row 5:] Rømer, 7.5, 60, Fahrenheit precursor with similarly random design, 4/10,
:[Row 6:] Rankine, 491.7, 671.7, Fahrenheit, but with 0°F set to absolute zero, 6/10
:[Row 7:] Newton, 0, 33-ish, Poorly defined, with reference points like "the hottest water you can hold your hand in", 7-ish/10
:[Row 8:] Wedgewood, –8, –6.7, Intended for comparing the melting points of metals, all of which it was very wrong about, 9/10
:[Row 9:] Galen, –4?, 4??, Runs from –4 (cold) to 4 (hot). 0 is "normal"(?), 4/–4
:[Row 10:] ''Real'' Celsius, 100, 0, In Anders Celsius's original specification, bigger numbers are ''colder''; others later flipped it, 10/0
:[Row 11:] Dalton, 0, 100, A nonlinear scale; 0°C and 100°C are 0 and 100 Dalton, but 50°C is 53.9 Dalton, 53.9/50

==References==
{{reflist}}

{{comic discussion}}

[[Category:Charts]]
[[Category:Science]]

Talk:2998: Ravioli-Shaped Objects

2024-10-19T19:07:12Z

162.158.33.225:

I think its a missed opportunity not to include the 'bulging lithium battery' themed throw pillow.[[User:Xurkitree10|Xurkitree10]] ([[User talk:Xurkitree10|talk]]) 22:04, 14 October 2024 (UTC)
: [https://www.google.com/search?sca_esv=455ef0c0e7ccb718&rlz=1C5CHFA_enPT1102PT1103&sxsrf=ADLYWILokQZ6eE3TWl2J_c07q1iHNDGgjw:1729080251272&q=%27bulging+lithium+battery%27+throw+pillow&udm=2&fbs=AEQNm0Aa4sjWe7Rqy32pFwRj0UkWd8nbOJfsBGGB5IQQO6L3J_TJ4YMS4eRay1mUcjRHkZwkNnuzbvXdHSnZt8SI-ypebpRXuYkgug6DK-4Ut13H99ktA8Mqi1OEFqdR-eK48bJa__90OMgplgEoZnWValhUQ343gp_exU8Evdjtace2RF7oLL9h99qRkTgUJWLIWwzoXToL&sa=X&ved=2ahUKEwj72qjx7ZKJAxVOYPEDHe8mDMkQtKgLegQINxAB&biw=1920&bih=968&dpr=1#vhid=fdx7hJP7669_DM&vssid=mosaic Oh, these actually exist]--[[Special:Contributions/172.64.236.35|172.64.236.35]] 12:07, 16 October 2024 (UTC)
:: Although technically, the pillow itself is normal, it's the overlay / cover which is battery themed. -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 05:08, 17 October 2024 (UTC)
::: Missing a trick by not having them be heated. [[Special:Contributions/172.70.90.202|172.70.90.202]] 08:49, 17 October 2024 (UTC)

Battery stories.
One of my backup batteries has started bulging so much I wrapped it in duct tape to hold the case onto it. It still works if I joggle the connectors well, but I’m worried.
Another time, I was trying to repair a cell phone but accidentally pierced the battery with my tiny screw driver. It started sparking and smoking and emitting dense dark noxious smoke. I threw it, it landed on a chair and burst into a small fire. The building filled with the dense noxious smoke, setting off all the alarms, coughing, opening the windows. When the fire calmed down (it didn’t spread) the chair seat was burnt in the shape of the battery, as well as the phone was bent and discolored and unusable in every way. But it still had its electronics in many parts. I want to image that flash chip and get my files!
A kid also once told me, they had an old phone they had taken to a very cold event (lithium batteries can hold power in proportion to temperature, so sudden drops could be a problem), and it started emitting s whining nosie. They threw it for safety, and it exploded away from them, according to their story.

Now, people also sell large expanded batteries for cell phones, which don’t fit in the case, and people mod or bend the case to get more power for their phones. Phone hacking, in some areas, has been getting easier and easier as information on it spreads and as design norms for phones stabilise. I used to mismatch phone batteries to save money and waste, but I was young and I would do crazy things like bunching up internal foil from candy wrappers, or bending paperclips, or pulling copper strands from discarded wires, and with my youngster manual dexterity i could measure the right voltages and jam, tape, or solder the disparate batteries to the internal connectors, and forcing the phone back on would then indeed yield things that looked like Randall’s drawings here.

Since traditional lithium batteries stop working after a few years, there’s pressure for people to do home battery mods.

But I bet nowadays you can find all sorts of clear descriptions of how to do these various things much better than I used to all over the internet somewhere, maybe even 3d print designs for parts. Maybe even a robot or drone exoskeleton for your phone, connecting with usb-serial or bluetooth or wifi.

So according to Randall it’s totally safe to use my bulging lithium backup battery (even if a screen is a little cracked)? {{unsigned ip|172.69.59.66|22:29, 14 October 2024}}

Should we create a group/series for comics containing confusion matrices? This now makes 5, with the other 4 being 2963, 2813, 2420 and 1890. [[Special:Contributions/108.162.250.184|108.162.250.184]] 22:50, 14 October 2024 (UTC)
:Nevermind I just realised that this group exists, my bad. [[Special:Contributions/172.68.210.124|172.68.210.124]] 22:53, 14 October 2024 (UTC)

I wasn't expecting a comic about spicy pillows but I think it's awesome that we got one. I do think there should be mention of or links to how to safely dispose of expanding lithium batteries such as [https://www.call2recycle.org/ Call2Recycle] in the explanation, even if it's just to spread awareness about the dangers of spicy pillows and the proper disposal of them. [[User:OmniDoom|OmniDoom]] ([[User talk:OmniDoom|talk]]) 23:36, 14 October 2024 (UTC)

spicy pillows yummy [[User:CalibansCreations|'''Caliban''']] ([[User talk:CalibansCreations|talk]]) 07:41, 15 October 2024 (UTC)

Shouldn’t the bottomright square be yellow or even red? (I see it is mentioned in the explanation already) - - [[Special:Contributions/172.71.103.178|172.71.103.178]] 09:26, 15 October 2024 (UTC)
: I'm assuming that Randal has the experience in his community of never having an issue with installing an expanded battery. The comic appears to be saying that rumors that this is dangerous are false. But I don't know, maybe he's getting senile. In the "internetizen" or "hacker" spirit of the comic's demographic, trying out alternative approaches than the mainstream is (or was) the celebrated norm, and leads to many new discoveries that are (or were) shared online. There might be more information on irc or twitter. [[Special:Contributions/108.162.245.129|108.162.245.129]] 23:17, 15 October 2024 (UTC)
:My interpretation is that yellow indicates "weird" rather than safe/practical. Two two yellow-marked squares are no unsafe or impractical, they are merely weird. Having a bulging phone battery is not weird, and because it still functions (despite being dangerous/damaging), it can't be red either. I do think it's an odd choice though, emotionally. [[User:Maplestrip|Maplestrip]] ([[User talk:Maplestrip|talk]]) 09:41, 16 October 2024 (UTC)

:When I visit https://xkcd.com/2998/ the bottom right cell is red not green as on this page. If something has been update this might warrent a trivia section.[[Special:Contributions/162.158.154.92|162.158.154.92]] 04:21, 19 October 2024 (UTC)

::More importantly, the image here should be replaced by the one Randall now has on his site.[[Special:Contributions/162.158.134.224|162.158.134.224]] 07:42, 19 October 2024 (UTC)

In the phone/pillow square, we can see an edge under the front of the pillow, so maybe Cueball split the phone opened and placed the pillow between the parts. That would explain the red color. [[Special:Contributions/162.158.127.99|162.158.127.99]] 12:43, 15 October 2024 (UTC)
:If the intent is to put each battery/non-battery-substitute 'in' the battery compartment, then this makes sense. Given that it's typically a tight-tolerance fit (so that even a slightly 'blown' battery is hard to insert, or at least get the cover back over), anything bigger than the original battery will protrude, or at least distort the case heavily. [[Special:Contributions/172.71.26.55|172.71.26.55]] 14:38, 15 October 2024 (UTC)

It seems like Randall forgot to hide the sketch in the bottom left cell. {unsigned ip|162.158.167.83|20:50, 15 October 2024}}

Please do not eat old Samsung batteries. [[User:Psychoticpotato|P?sych??otic?pot??at???o ]] ([[User talk:Psychoticpotato|talk]]) 21:01, 15 October 2024 (UTC)
:Nor drink, nor use as headrests. Thank you fandoor your cooperation. [[Special:Contributions/172.68.22.191|172.68.22.191]] 23:50, 15 October 2024 (UTC)

: Eating a lithium (IIRC) battery is good for one and those about iff one is a zombie in Z Nation ( https://www.imdb.com/title/tt3843168/ ) Otherwise? Yikes.
:Aside: I'd advise against thinking that xkcd is an advice column. [[Special:Contributions/172.70.134.213|172.70.134.213]] 02:58, 16 October 2024 (UTC)

:Please do not eat other brand of lithium batteries either, no matter their age. Do not eat Apple batteries. Do not eat Google Pixel batteries. Do not eat Xiaomi batteries. Do not eat Huawei batteries. Do not eat Honor batteries. Do not eat Motorola batteries. Do not eat rechargable AAA batteries. Actually, do not eat non-rechargable AAA batteries either, although those are not lithium-based. -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 05:15, 17 October 2024 (UTC)
::Nor AAs, CR2032s or PP3s. Although I suspect that {{w|D battery|D cells}} are perfectly ok, so long as you don't try to chew them and just swallow them whole... [[Special:Contributions/172.70.90.202|172.70.90.202]] 05:45, 17 October 2024 (UTC)
We need a row for cooking them because baked lithium ion batteries are tasty (The Batteries from those old T-mobile keyboard phones are the best kind they have extra flavor) {{unsigned|TiredQuill281|20:13, 18 October 2024}}

Would someone who has the necessary privileges please update the image file? The bottom-right square has changed colour. [[User:BunsenH|BunsenH]] ([[User talk:BunsenH|talk]]) 16:01, 19 October 2024 (UTC)
:And, when done, it would be good to link the <code><nowiki>[[original image file]]</nowiki></code>, appropriately, in the text that currently explains the change.
:Normally, the picture would be updated and an addendum paragraph and/or Trivia item would be given to explain how it originally was before the 'correction', but the change is documented within the table already.
:Although yet another option would be to clean up that (perhaps overlong) cell to be just the "it is red" paragraph, and actually transfer into a Trivia statement the whole extracted "originally it was [color]green[/color], rather than [color]red[/color] or [color]yellow[/color]..." bit, slightly adjusted for Trvica-scope context. [[Special:Contributions/162.158.33.224|162.158.33.224]] 18:18, 19 October 2024 (UTC)
:Ok, direct followup to the above (162.158.33.224), which was me. I've just done what I suggested. "Originally the image was..." stuff sent into Trivia (with my own little touches and interpretations - feel free to edit as required!) and slightly compressed what was left in the changed tile's table-cell (again, could be refined, but I tried to put both "warnings about fire" in a narratively continuous context, rather than split across paragraphs). [[Special:Contributions/162.158.33.225|162.158.33.225]] 19:07, 19 October 2024 (UTC)

2998: Ravioli-Shaped Objects

2024-10-19T18:09:37Z

162.158.33.225: /* Explanation */ Highlighting the non-red colours. Fiddling with the reasons (and non-reasons) a bit for better flow.

{{comic
| number = 2998
| date = October 14, 2024
| title = Ravioli-Shaped Objects
| image = ravioli_shaped_objects_2x.png
| imagesize = 608x569px
| noexpand = true
| titletext = It's a real accomplishment to mess up a ravioli recipe badly enough that the resulting incident touches all four quadrants of the NFPA hazard diamond.
}}

==Explanation==
{{incomplete|Created by a BULGING LITHIUM BATTERY THROW PILLOW BEING EATEN WITH A FORK- Ideally the article would contain grounded explanations of both of the views that bulging lithium batteries are either dangerous or safe. How would an explosion happen, or why would it not? Please change this comment when editing this page. Do NOT delete this tag too soon.}}
{{w|Ravioli}} are a kind of stuffed {{w|pasta}} comprising a filling enveloped in thin pasta dough, commonly square shaped, and serving as the object of this comic's table, which can be seen as a kind of {{w|confusion matrix}}. This comic compares four ravioli-shaped objects (square shaped objects with bulging cross-sections due to their filling) with some common actions associated with them.

{| class="wikitable" | style="background:#E6C3C3;"
! Ravioli-Shaped Objects
! scope="col"| Eat with a fork
! scope="col"| Rest your head on
! scope="col"| Puncture and slurp
! scope="col"| Install in your phone
|-
! scope="row"| {{w|Ravioli}}
| style="background:#C5E6C3;"|Ravioli pasta would indeed be suitable to be eaten with a fork, as shown.
|Ravioli pasta is not structurally strong enough to support the weight of a human head while reclining, and would break and spill its filling over one's head and the object one is resting on. It may also be covered in sauce, adding to the general mess.
|style="background:#FBF8CE;"|If the ravioli filling is fluid enough, one could slurp it out with a straw. This would waste the pasta component, if it were not eaten afterwards.
|Phones are not meant to run on ravioli. Stuffing a phone with a raviolo would cause it to break as shown, spilling the filling through the phone, which is a terrible idea.
|-
! scope="row"| {{w|Throw pillow}}
|Throw pillows are made of cloth and are inedible, whether one uses a fork or not.
| style="background:#C5E6C3;"|A throw pillow is meant to be used as head support while reclining on furniture.
|Throw pillows do not usually have liquids inside them. Hence, Cueball finds, to his dismay, that it's empty.
|Throw pillows are significantly bigger than phones and as such can't fit inside them, nor can typical pillows power them. As depicted, the attempt to force a pillow inside the phone has split the latter in half; the top half of the phone is visible on top of the pillow, and a bit of the bottom half can be seen beneath it.
|-
! scope="row"| {{w|Capri Sun}}
|Eating a pouch of sweetened juice with a fork would most likely simply pierce the pouch and spill the liquid all over Cueball.
|style="background:#FBF8CE;"|A Capri Sun would serve as a waterbed of sorts, and wouldn't be unduly uncomfortable in a pinch. However, it's still possible that the pouch could rupture and leave you with a sticky head and no support.
|style="background:#C5E6C3;"|Capri Suns are meant to be drunk like this, and are enjoyed by many.{{citation needed}}
|The phone shown is surrounded by spilled Capri Sun, implying that the attempt to force the two together punctured the pouch. The resulting spillage would most likely just result in the surface of the phone becoming annoyingly sticky, but if the liquid managed to get inside the phone (especially if the cover had been removed to try to put it in the compartment that usually holds the battery) it could cause a more significant and difficult to clean mess. Once actual power is provided (either an actual battery being subsequently used or the device offered external power by cable or inductance charger), the remaining residue could cause any number of further faults, and perhaps even critical component damage.
|-
! scope="row"| Bulging {{w|Lithium Battery}}
|Bulging lithium batteries are explosive hazards and should not be punctured lest they explode. Additionally the contents of the battery are toxic if one were to somehow manage to eat the burning bits of the battery.
|A lithium battery is a small, hard object, and a bulging one is no exception. Since the bulging comes from a buildup of heat and gas, (the primary gases being hydrogen and carbon dioxide), it would also be a constant fire hazard, which would not be conducive to relaxation.{{cn}} Lithium battery themed throw pillows, which bulge similarly to such batteries, do exist as a novelty item. Notably, these types of batteries are often referred to as "spicy pillows".
|Similarly to the 'eat with a fork' example, puncturing a bulging lithium battery is a bad idea.
|A bulging lithium battery could be installed in a phone, if one is willing to break the phone a bit (like the screen in the comic) to accommodate the bulging of the battery. Also a terrible idea, as operating the lithium battery in this condition may result in the battery [https://www.reading.ac.uk/health-safety-services/fire-safety/lithium-battery-information/i-have-a-swollen-lithium-ion-battery-what-should-i-do catching fire or worse]. More commonly, bulging batteries form inside the phone itself, causing it to bulge outwards.
Surprisingly, this square was initially marked in green, rather than red or yellow, when it was first uploaded. But the first thing one should do on noticing bulging of the battery is to uninstall it from any device that it is in. It is at least no longer good at holding/delivering its charge, and may even become at least as {{w|Lithium-ion battery#Fire hazard|hazardous}} as when used in all the other scenarios. This square may have been marked in green because, although putting a bulging battery in a mobile phone is not normal usage, it's a situation that can arise ''from'' normal usage when a "healthy" battery begins to fail (one other suggestion was that this was an [[:Category:xkcd Phones|xkcd phone]], and a dodgy battery is part of a 'feature', such as an 'integrated hand warmer' or 'dynamic expansion'). More likely, it was just because Randall unthinkingly went with "Row N is appopriate for Column N", as is the [[:Category:Confusion matrices|usual design]] for these comics, plus adjustments for other surprises/exceptions.
|}

The title text refers to the {{w|NFPA 704}} diagram for hazardous materials, a diamond figure put out by the {{w|National Fire Protection Association}} showing four kinds of fire hazards. A ravioli that touched all four quadrants would be a health hazard, fire hazard, and demonstrate (chemical) reactivity, and have some other miscellaneous hazard(s). The NFPA diamond was previously mentioned in [[2638: Extended NFPA Hazard Diamond]].

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:[A 4x4 grid of squares. The columns are labeled: Eat with a fork, rest your head on, puncture and slurp, install in your phone. The rows are: Ravioli, throw pillow, Capri Sun, bulging lithium battery. Each row has an image of each respective item above the title, with the words “Home Sweet Home” on the throw pillow, and “Fruit” on the Capri Sun.]

Top-Left
:Ravioli, eat with a fork: [green]
::[Cueball sits on a chair in front of a table with a jar of sauce on it. He is eating from a plate from ravioli.]
::Cueball: ''Nom Nom Nom''

Top Mid-Left
:Ravioli, Rest your head on: [red]
::[Cueball is lying down on a couch with ravioli smooshed on his head and the couch. Ravioli bits can be seen on the ground]
::Cueball: Eww.

Top Mid-Right
:Ravioli, puncture and slurp: [yellow]
::[Cueball is slurping from a ravioli through a straw. In front of him is table with two plates, presumably with ravioli on them.]
::''Slurp''

Top-Right
:Ravioli, Install in your phone: [red]
::[A phone is shown with bits of ravioli sticking out and tomato sauce is dripping out.]

Top-Mid Left
:Throw pillow, eat with a fork: [red]
::[Cueball sits on a chair in front of a table with a jar of sauce on it. He is poking with a fork at a throw pillow covered in tomato sauce.]
::''Poke poke''

Top-Mid Mid-Left
:Throw pillow, rest your head on: [green]
::[Cueball is looking at his phone and is lying on a couch. His head is resting on a throw pillow.]

Top-Mid Mid-Right
:Throw pillow, puncture and slurp: [red]
::[Cueball is sucking on a straw that is inserted in a pillow.]
::Cueball: Aw man, this one is empty.

Top-Mid Right
:Throw pillow, install in your phone: [red]
::[A phone is shown on a throw pillow that has the words “Home Sweet Home” partially obscured.]

Bottom-Mid Left
:Capri Sun, eat with a fork: [red]
::[Cueball sits on a chair in front of a table with a jar of sauce on it. He has stabbed a Capri Sun on a plate and is now splattered with juice.]

Bottom-Mid Mid-Left
:Capri Sun, rest your head on: [yellow]
::[Cueball is looking at his phone and is lying on a couch. His head is resting on a Capri Sun.]
::Cueball: Honestly kind of comfortable.

Bottom-Mid Mid-Right
:Capri Sun, puncture and slurp: [green]
::[Cueball is drinking from a Capri Sun through a straw.]
::''Sluuurp''

Bottom-Mid Right
:Capri Sun, Install in your phone: [red]
::[A phone is shown to be squishing a Capri Sun. Juice is trickling out.]

Bottom Left
:Bulging lithium battery, eat with a fork: [red]
::[An explosion bordered by 4 skull and crossbones.]

Bottom Mid-Left
:Bulging lithium battery, rest your head on: [red]
::[Cueball is looking at his phone and lying on his couch. His head is resting on a smoldering battery.]
::Cueball: This fire hazard is uncomfortable.

Bottom Mid-Right
:Bulging lithium battery, puncture and slurp: [red]
::[An explosion bordered by 4 skull and crossbones.]

Bottom Right
:Bulging lithium battery, install in your phone: [red]
::[A phone with a bulging back, presumably from the bulging lithium battery. The phone’s screen is cracked in the center.]

{{comic discussion}}

[[Category:Comics with color]]
[[Category:Confusion matrices]]
[[Category:Comics featuring Cueball]]
[[Category:Food]]
[[Category:Phones]]