Editing 2539: Flinch

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==Explanation==
 
==Explanation==
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{{incomplete|Created by a WOUNDED POSTMED STUDENT - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
  
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[[Cueball]] is performing [https://youtu.be/4a0FbQdH3dY?t=1518 a common physics demonstration] in which a heavy ball is hung from a rope or cable. The demonstrator, or a volunteer, pulls the ball back until it's close to their face (possibly even touching it), then releases it, allowing it to swing, and then return. Due to conservation of energy, the ball cannot return any further than its original release point, making it impossible for the person to be struck by it. Because a heavy pendulum will tend to lose little energy on each swing (relative to its overall energy), it will come back very close to its original point, so the experiment creates a conflict between the instinctive desire to escape a heavy object flying at your face, and the theoretical knowledge that it won't harm you.  
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[[Cueball]] is performing [https://youtu.be/4a0FbQdH3dY?t=1518 a common demonstration of conservation of energy] to a group of bystanders with different science backgrounds: A bowling ball hung on a pendulum. He asks if they'll flinch after the ball is released and swings toward them on its return arc. Black Hat sets up a bowling ball pendulum in [[1670: Laws of Physics]], but sets it up improperly on purpose in an attempt to hurt Cueball.
  
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[[Megan]] is a physicist, who understands the principles of the experiment and claims she won't flinch, confident that it can't harm her.
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The first bystander, a physicist ([[Megan]]) understands the principles of the experiment and claims she won't flinch. She knows that, as long as it's just ''released'' (as opposed to being pushed) in still air, then the ball won't return further than its point of release.  (If the experiment is conducted outdoors, then it is possible for a sudden wind gust to blow the ball enough for it to return further than its point of release; however, this is unlikely with a bowling ball, which has a large mass compared to its surface area.)
  
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[[Hairy]] is a biologist, and implies that he has no intention of avoiding the flinch reflex, as he trusts the {{w|Reflex|automatic reflexes}} that the human body has evolved more than he trusts the premise of the experiment. In both [[755: Interdisciplinary]] and [[1670: Laws of Physics]], the same experiment is referenced. In the title text of the latter [[Randall]] makes a very similar argument as the biologist does here.  
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The second bystander, a biologist ([[Hairy]]) seems to indicate that he expects to flinch, but he feels this is natural and doesn't intend to fight it. It is natural, and in fact the body comes with many kinds of {{w|Reflex|automatic reflexes}}. In [[1670: Laws of Physics]], Randall makes a very similar comment in the title text.  
  
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[[Ponytail]], an engineer, replies that she doesn't trust Cueball to have hung the pendulum correctly.  Engineers are trained in science, but work with practical applications, and tend to be very aware that practice is rarely as simple as scientific theories might imply. Even if the physical laws are constant, the experiment might not go according to plan. For example, if the cable were to snap or come loose while swinging toward the subject, the ball could strike them in the body, or land on their feet.  If the cable is more elastic than anticipated, it could stretch unpredictably, once again striking someone.  If the anchor point is not stable, it could shift during the experiment, once again causing harm. Also if the ball is not released but pushed, or if the one releasing it leans forward after release they might get hit in the face.
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The third bystander, an engineer ([[Ponytail]]), knows practice usually differs from theory.  She answers Cueball's
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question by declaring that she doesn't trust him.  Cueball is holding the ball so the
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string is visibly curved, not stretched, as when the ball pendulums back.  The string and ball
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thus start with greater gravitational potential energy (height) and elastic potential energy
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than when the ball swings back to the same position over the floor.
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The excess energy means a near even chance the ball may move past its starting point on
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the first swing, and sometimes pass or not on following swings.
  
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The punch line basically makes the point that failure to trust the safety of an experiment doesn't necessarily imply a lack of scientific knowledge. If you lack confidence in the design of an experiment, then it's not safe to assume that the laws of physics will protect you.
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In the title text, a premed student tries to get course work done. {{w|Pre-medical}} university courses require students to undertake a certain amount of study in specific areas; one of those areas being physics. They also have a reputation for being more intensive than other undergraduate degrees, so the student is portrayed as being very stressed and time-conscious. They ask if participating in the demonstration will contribute towards their course credit in physics, the implication being they do not consider it worthwhile otherwise.  
  
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The comic as a whole demonstrates that members of different disciplines have differing perspectives on the world: Physicists trust physics, biologists trust biology, and engineers do ''not'' trust engineering. This creates irony, because the reader might expect that an engineer would trust engineering, but in actuality, engineers distrust things designed by humans, since they so often design things poorly and/or encounter things others have designed poorly.
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Shortening the string the ball is suspended from would shorten the period of the pendulum, thus reducing the time it takes to complete the demonstration. Again the student asks if this can be done to save time, although obviously the few seconds difference made would be utterly inconsequential within the context of an entire degree.
  
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The title text shows a pre-med student's response. {{w|Pre-medical}} university courses have a reputation for being more intense and demanding than other undergraduate degrees, so the student is portrayed as being very stressed and time-conscious; showing little interest in the experiment itself, only in how it impacts their degree. In addition, medical students are commonly the subject of "interesting" medical experiments which may lead to long-term psychological and physical side-effects.
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They also ask if they can do a variant of the demonstration where they ''are'' deliberately hit in the face. This would likely injure them, but they want to use this to their advantage because they have a "thing for first aid training" after the demonstration. It's not clear how this would help, although it could potentially help ''others'' learn first aid by having them practice on the new injury.
  
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The student first asks if participating in the demonstration will count for a physics credit, implying that they're not willing to spend time on it unless it contributes to their academic requirements. They then ask if they can shorten the string to make the demonstration go faster. Shortening a pendulum does, indeed, cause it to swing faster, but the time saved would be less than the time necessary to make the modification, so the demonstration would not end sooner. Finally, they ask to do a variant where they ''deliberately'' get struck in the face, because they have a "thing for first aid training" immediately after. This would likely injure them, but the student is apparently willing to sacrifice their own safety and well-being in service to their academic career. It's not clear how this would help, although it could potentially help ''others'' learn first aid by having them practice on the new injury.
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==Transcript==
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{{incomplete transcript|Do NOT delete this tag too soon.}}
  
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Various alternate takes on this experiment have been previously featured in [[755: Interdisciplinary]] and [[1670: Laws of Physics]], but this is the first time experiment is performed in a proper manner.
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:[Cueball holds a bowling ball attached to a string. He is talking to Megan, Hairy, and Ponytail. Between Cueball and the other three is a cross in a circle on the floor.]
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==Transcript==
 
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:[Cueball holds a bowling ball in both hands. It is attached to a string that goes behind him and up disappearing off panel around double his height. He is talking to Megan, Hairy, and Ponytail who is looking at him. Between Cueball and the other three is a cross in a dotted circle on the floor.]
 
 
:Cueball: If you stand with the bowling ball in front of your face and let go, will you flinch when it swings back?
 
:Cueball: If you stand with the bowling ball in front of your face and let go, will you flinch when it swings back?
  
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:[Zoom in on Megan in a slim panel. There is a caption in a frame above her.]
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:[Caption: Physicist]
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:Caption: Physicist
 
 
:Megan: I won't flinch.
 
:Megan: I won't flinch.
 
:Megan: I trust conservation of energy.
 
:Megan: I trust conservation of energy.
  
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:[Zoom in on Hairy, in a wide panel. He has lifted arm holding his hand palm up toward Cueball (who is off-panel). There is a caption in a frame above him.]
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:[Caption: Biologist]
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:Caption: Biologist
 
 
:Hairy: I trust my flinch reflex, which was honed by millions of years of evolution to protect my delicate face. I'm not messing with it.
 
:Hairy: I trust my flinch reflex, which was honed by millions of years of evolution to protect my delicate face. I'm not messing with it.
  
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:[Zoom in on Ponytail in a slim panel. There is a caption in a frame above her.]
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:[Caption: Engineer]
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:Caption: Engineer
 
 
:Ponytail: I don't trust that you hung that thing up correctly.
 
:Ponytail: I don't trust that you hung that thing up correctly.
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{{comic discussion}}
 
{{comic discussion}}
  
 
[[Category:Comics featuring Cueball]]
 
[[Category:Comics featuring Cueball]]
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[[Category:Comics featuring Hairy]]
 
[[Category:Comics featuring Megan]]
 
[[Category:Comics featuring Megan]]
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[[Category:Comics featuring Hairy]]
 
 
[[Category:Comics featuring Ponytail]]
 
[[Category:Comics featuring Ponytail]]
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[[Category:Physics]]
 
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[[Category:Biology]]
 
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[[Category:Engineering]]
 

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