Editing 226: Swingset

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{{comic
 
{{comic
 
| number    = 226
 
| number    = 226
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| date      = February 21, 2007
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| date      = 2007-02-21
 
| title    = Swingset
 
| title    = Swingset
 
| image    = swingset.png
 
| image    = swingset.png
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==Explanation==
 
==Explanation==
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In the opening panel of this comic, [[Blondie]], possibly as [[Miss Lenhart]], sees [[Cueball]] sitting on a swing set. She tells him that during his swing, he becomes weightless. Cueball then imagines that at the peak of his swing he is able to become permanently weightless, floating above the ground without any support.
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When on a swing, there is a moment between swinging forwards/backwards and falling back down again where the the force of gravity stops the acceleration of the swing. In this moment, you remain almost stationary at the peak of your swing and on a perfect swing (ie. one with no friction or air resistance) you would achieve weightlessness.
  
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When on a swing or other [http://www.learner.org/interactives/parkphysics/pendulum.html pendulum ride], there is a moment between swinging forwards/backwards and swinging back down again when the forces of gravity, friction, air resistance, etc., bring the velocity of the swing to zero. At this moment, there is no acceleration toward the pivot of the swing (since the centripetal acceleration is proportional to the square of the speed). So the swinger experiences no centripetal force. Of course, gravity still acts on the person, but if the swing is horizontal at that point, then there is no reaction force, so for one moment, the swinger is in free-fall and experiences {{w|weightlessness}}. However, that weightlessness can only be maintained for a fraction of a second, so if Cueball tried this in real life, he would come crashing to the ground.
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In the comic, [[Cueball]] is told this fact by an unknown woman and then imagines that at the peak of the swing you become permanently weightless and able to float above the ground without any support.
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In the title text, Cueball asks for a pocket fan, believing he could fly around the yard using this small device perhaps as a propeller. By using the fan to blow air in the opposite direction he wishes to travel, he could perhaps use the reaction force to push himself around.
 
  
 
==Transcript==
 
==Transcript==
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:[Woman talking to Cueball on swing-set.]
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:[Woman talking to boy on swing-set]
 
:Woman: You know, at the peak of a big swing, you become weightless.
 
:Woman: You know, at the peak of a big swing, you become weightless.
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:[Thought bubble from Cueball.]
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:[Thought bubble from boy on swing-set]
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:[Cueball swings higher and higher. At the peak of a big swing, he shoves himself off the swing. Cueball remains hovering in the air.]
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:[Boy swings higher and higher. At the peak of a big swing he shoves off the swing. The boy remains hovering in the air.]
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:Cueball: Hey guys. Come check this out.
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:Boy: Hey guys. Come check this out.
  
 
{{comic discussion}}
 
{{comic discussion}}
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[[Category:Comics featuring Cueball]]
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<!-- Include any categories below this line. -->
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[[Category:Physics]]
 

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