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==Explanation==
 
==Explanation==
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This comic is the 17th comic in a row (not counting the [[2288: Collector's Edition|April Fools' comic]]) in a [[:Category:COVID-19|series of comics]] related to the {{w|COVID-19 pandemic}}.
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{{incomplete|Created by a ROGUE RADIAN. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.}}
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This comic expresses frustration at the multitude of {{w|temperature}} scales. [[Randall]], as a former engineer, has strong opinions about units, as unit conversion is often a gripe for many engineers. (In a special preface in the UK edition of Randall's book ''What If'', he mentions that one does not appreciate the metric system unless they have had to go through a bunch of scientific papers using really unusual units like "kilocubic feet per second" or "acre-feet".) As elevated body temperature is a symptom of {{w|COVID-19}}, the comic is additionally the 17th in a row concerning the virus.
  
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This comic expresses frustration at the multitude of {{w|temperature}} scales. [[Randall]], as a former engineer, has strong opinions about units, as unit conversion is often a gripe for many engineers. (In a special preface in the UK edition of Randall's book ''What If'', he mentions that one does not appreciate the metric system unless they have had to go through a bunch of scientific papers using really unusual units like "kilocubic feet per second" or "acre-feet".) As elevated body temperature is a symptom of COVID-19, the comic is thus also concerning the virus.
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[[Cueball]] may be sick or ill, and is trying to check his {{w|Human body temperature|body temperature}}, but he is unclear what the results mean. Cueball's {{w|thermometer}} has several units, of which the four shown humorously grow progressively less useful:
  
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[[Cueball]] is holding what appears to be a medical thermometer, implying that he's trying to check his {{w|Human body temperature|body temperature}}. He mentions that the thermometer is in Celsius, and asks how to change it.  Many thermometers sold in the United States have settings for both Fahrenheit and Celsius, with an option to change between the two. Americans are almost always more familiar with body temperatures in Fahrenheit, so Cueball presumably expects to change to that scale. However, he finds that the thermometer provides measurements in a series of scales that are increasingly unhelpful. Human body temperature in Celsius is 37 °C.
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*Degrees {{w|Celsius}} are used in most of the world. The Celsius scale sets 0 degrees to water's freezing point and 100 degrees to water's boiling point.  Randall lives in Boston, USA, one of the few countries where Celsius is not used for health measurements. In the USA, health-relevant temperatures are almost always discussed in Fahrenheit.
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*{{w|Kelvin}} is a unit often used in scientific fields. It is the basis for the Celsius scale, with 1 Celsius degree equivalent to 1 (degree) kelvin, where 0 K is {{w|absolute zero}} or -273.15 °C.
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*The {{w|Rankine scale}} is similar to Kelvin but far less well known. It starts at absolute zero, 0°R, equal to -459.67 °F, with a change of 1° Rankine equal to a change of 1° Fahrenheit.
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*Thermodynamically, temperature is the average translational {{w|kinetic energy}} of a group of particles. ''Translational'' kinetic energy means it doesn’t include rotational kinetic energy. The relation between a gas’s kinetic energy and its temperature is described by the {{w|Boltzmann constant}}, 1.380649×10<sup>−23</sup> J⋅K<sup>-1</sup>. So if this thermometer told you a translational kinetic energy measurement in joules, you could get the measured temperature in the Kelvin scale by dividing by the Boltzmann constant.  
  
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*Degrees {{w|Celsius}} are used in most of the world. The Celsius scale sets 0 degrees to water's freezing point and 100 degrees to water's boiling point. Few Americans have a clear idea of what normal and elevated ranges of human body temperature are in Celsius.
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Using these last three units for home temperature gauging would be ridiculous, as Kelvin and Rankine measurements of body temperature are far too large and uncommon to be practical for the average user, while kinetic energy is obscure enough that only a relative handful of physicists and thermodynamicists would likely know it. Those that do could make use of the value printed on the thermometer, but again extremely few people would know enough to make use of this.
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*{{w|Kelvin}} is a unit often used in scientific fields. It is calibrated on the same scale as degrees Celsius, but 0 K is set at {{w|absolute zero}} or -273.15 °C. This is used in scientific or engineering contexts requiring a thermodynamically absolute temperature, such as {{w|Charles's law}}, but almost never in a medical context, making the report of little use.
 
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*The {{w|Rankine scale}} is another absolute scale, with its zero set at absolute zero, but degrees identical to degrees Fahrenheit. While this scale is still occasionally used in some industrial and scientific settings (being more convenient for absolute temperatures in a system including Fahrenheit), it's essentially never used in medicine, and most people have never heard of it.
 
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*Thermodynamically, temperature is the average translational {{w|kinetic energy}} of a group of particles. ''Translational'' kinetic energy means it doesn’t include rotational and vibrational kinetic energy. The relation between a gas’s translational kinetic energy E and its temperature T is
 
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::<math>E=\frac32 k_B T,</math>
 
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:where k<sub>B</sub> is the {{w|Boltzmann constant}}, 1.380649×10<sup>−23</sup> J⋅K<sup>-1</sup>. So if this thermometer told you a translational kinetic energy measurement in joules, you could get the measured temperature in the Kelvin scale by dividing by the Boltzmann constant and multiplying by 2/3. Somebody who actually wanted to use this measure of temperature might then find it useful to have Boltzmann's constant printed on the thermometer.
 
  
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Using these last three units for home temperature gauging would be ridiculous, as Kelvin and Rankine measurements of body temperature are unfamiliar to the average user and even those familiar with them would need to do calculations to translate normal body temperature. Kinetic energy is obscure enough that only physicists, engineers and thermodynamicists, a relative handful of the potential buyers, would likely know what it refers to. Those that do could make use of the value printed on the thermometer, but such would add a great deal of unnecessary complexity to what should be a simple and intuitive task.  
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In the last frame Cueball calls the thermometer the worst. It seems to lack {{w|Fahrenheit}} entirely, frustrating a huge chunk of its consumer base, including Cueball. From a nerd's perspective this would be an extraordinary device, offering even exotic temperature scales. However, a "normal person" would find this thermometer terribly difficult to use for everyday purposes when set on any of the non-Celsius scales, like checking their body temperature or the temperature of food. As an item of consumer electronics, especially one sold in the United States, it would be almost completely useless.  
  
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In the last frame Cueball calls the thermometer the worst. It seems to lack {{w|Fahrenheit}} entirely, frustrating its American consumer base, including Cueball. From a nerd's perspective this would be an extraordinary device, offering even exotic temperature scales. However, a "normal person" would find this thermometer terribly difficult to use for everyday purposes when set on any of the non-Celsius scales, like checking their body temperature or the temperature of food. As an item of consumer electronics, especially one sold in the United States, it would be almost completely useless.  
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Deliberately lacking Fahrenheit is a jab against the {{w|Imperial system of units}}; many proponents of the Metric system have been calling for Imperial units to be abolished for quite a long time now. Fahrenheit defines 32°F as the freezing point of water and 212°F as the boiling point of water at 1 atmosphere pressure; these are both artifacts of {{w|Daniel Gabriel Fahrenheit|Daniel Fahrenheit}}'s personal quirks and the practices of his time (he wished for 0 degrees to be a low as possible, and multiples of 6 were considered more satisfactory than multiples of 10) rather than any modern-day commonly-used baseline. Fahrenheit is retained in the United States mostly out of tradition -- nobody who uses it ''wants'' to change -- but does hold legitimate advantages: the smaller granularity between two degrees Fahrenheit can make for more convenient measuring at a glance, especially when measuring the ambient temperatures between 0°F and 100°F.
  
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Deliberately lacking Fahrenheit is a jab against the {{w|Imperial system of units}}, and against the similar but distinct system of {{w|United States customary units}}. Although Imperial units and local traditional units are still used for various limited purposes (and/or by older generations) in different countries, most of the world has switched to using the metric system for most purposes going forward, with the US being relatively unusual in the extent to which it still routinely defaults to the US customary units in daily life.  Many proponents of the metric system have long pushed for the US to change over, arguing that Imperial and US customary units (and degrees Fahrenheit, specifically) are archaic and obsolete. [[Randall]] has dealt with this conflict in [[1643|other strips]]; as a physics major, he's partial to the metric system, and finds it frustrating to maintain multiple different scales (which is the basis of the conflict in this strip). On the other hand, he recognizes certain intuitive advantages to Imperial and US customary measurements, and recognizes that the forces of social inertia in US society make change difficult.
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The title text references an archaic temperature unit, {{w|Rømer scale|Rømer}}, a scale proposed in 1701 whose fixed points are 7.5°Rø as water's freezing point and 60°Rø as water's boiling point. A degree on the Rømer scale is 40/21 of a degree on the Celsius scale. Early definitions of Fahrenheit used a rescaled Rømer scale, based on the temperature of freezing brine and human body temperature.
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The title text references an archaic temperature unit, {{w|Rømer scale|Rømer}}, first proposed in 1701. It is the common ancestor of both the Celsius and Fahrenheit scales, defining the freezing point of water as 7.5 degrees and the boiling point of water as 60 degrees. Unlike the other measurements mentioned in this strip, the Rømer scale is no longer used in any context, and only people interested in the history of temperature scales have any idea that it even exists. This is the ultimate form of obscure and outdated temperature measurements.
 
  
 
==Transcript==
 
==Transcript==
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{{incomplete transcript|Do NOT delete this tag too soon.}}
 
:[Cueball stands in the center of the panel holding a thermometer.]
 
:[Cueball stands in the center of the panel holding a thermometer.]
 
:Cueball: This thermometer is in Celsius. How do you change it?
 
:Cueball: This thermometer is in Celsius. How do you change it?
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{{comic discussion}}
 
{{comic discussion}}
 
[[Category:Comics featuring Cueball]]
 
[[Category:Comics featuring Cueball]]
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[[Category:COVID-19]]
 
 
[[Category:Science]]
 
[[Category:Science]]
 
[[Category:Physics]]
 
[[Category:Physics]]

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