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Twisted Logic Contradiction - any explanations
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sep...@yahoo.com
Jan 25, 2023, 7:35:15 PM1/25/23
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I posted a similar problem but no one explained things in a logical way. So I'm trying again. This time I have three scenarios with the similar contradictions. Please explain how physicists explain the results seen by observers in two inertial reference frames. I'm especially curious about the third scenario.
Scenario 1:
In inertial reference frame F0 there are two massive steel discs of diameter D, each centered on the x-axis a distance L apart along the x-axis. Between the two discs and touching each disc is a long cylinder of soft clay of length L also of diameter D. Along the x-axis is a steel rod attached to the center of each disc. The two discs, the clay cylinder and rod rotate about the x-axis at 10 revolutions per second. Just above the cylinder and discs and not touching them is an elastic band that extends parallel to the x-axis from one disc to the other disc.
There is a second inertial reference frame, F1, moving along the x-axis relative to F0 at a speed V = c*sqrt(3)/2. The distance L in F0 is such that events that occur one second apart as measured in F0 and are separated by L as measured in F0 occur simultaneously as measured in F1.
Now in F1 observers in F1 simultaneously attach each end of the elastic band to the two rotating discs and all points of the elastic band simultaneously to the surface of the rotating clay cylinder. After the elastic band is attached that way, observers in F1 see that the elastic band is always parallel to the x-axis as it rotates about the x-axis. Observers in F0 saw that one end of the elastic band was attached and that end made 10 revolutions around the x-axis before the other end was attached. So they observe that the elastic band spirals around the clay cylinder.
Now at the point on the disc on the left where the elastic band is attached, a force is applied to pull that end of the elastic band in the negative x direction. The elastic band is pulled past this point but the point on the disc where the pulling force is applied remains at the same position on the disc. This causes the elastic band that is spiraling around the soft clay cylinder (as observed in F0) to cut into the soft clay. As the elastic band is continually pulled, the elastic band will cut through the clay until it is a straight line as observed in F0, touching the rod connecting the two discs at the midpoint between the two discs.
Please explain why observers in F1 observe that the elastic band is parallel to the x-axis before the pulling occurs, but cuts through the clay instead of remaining on the clay's surface and parallel to the x-axis as the elastic band is pulled.
Scenario 2
The setup is identical to scenario 1. But in this scenario, observers in F0 simultaneously attach both ends and all points in between of the elastic band to the discs and the rotating clay cylinder. They observe that the elastic band and all points of it are parallel to the x-axis. Observers in F1 see the elastic band spiral about the cylinder. Now when a force at the left disc where the elastic band is applied to pull the elastic band in the negative x direction observers in F0 see that the elastic band always remains on the surface of the clay cylinder. Why do observers in F1, say that the spiraling elastic band never cuts through the soft clay as this force is continually pulling on the elastic band?
Scenario 3
This scenario is similar to scenario 1 but instead of a soft clay cylinder, there is a cylinder made of ice, and there are two elastic bands just above the cylinder running parallel to the x-axis. The two elastic bands are side by side separated by 1 cm. There is no rod between the two rotating discs in this scenario.
In F1, observers attach all points of the two elastic bands simultaneously to the two rotating discs and the surface of the rotating ice cylinder. They observe that the two elastic bands are always parallel to the x-axis. Now the ice melts and disappears. Let there be a force on the two points of the left disc where the elastic bands are attached that pulls each band identically in the negative x-direction. Now the two elastic bands will eventually be observed to wrap around each other 10 times. How do observers in F1 say that two parallel bands could possibly wrap themselves around each other 10 times in this scenario?
Thanks,
David Seppala
Bastrop TX
Scenario 1:
In inertial reference frame F0 there are two massive steel discs of diameter D, each centered on the x-axis a distance L apart along the x-axis. Between the two discs and touching each disc is a long cylinder of soft clay of length L also of diameter D. Along the x-axis is a steel rod attached to the center of each disc. The two discs, the clay cylinder and rod rotate about the x-axis at 10 revolutions per second. Just above the cylinder and discs and not touching them is an elastic band that extends parallel to the x-axis from one disc to the other disc.
There is a second inertial reference frame, F1, moving along the x-axis relative to F0 at a speed V = c*sqrt(3)/2. The distance L in F0 is such that events that occur one second apart as measured in F0 and are separated by L as measured in F0 occur simultaneously as measured in F1.
Now in F1 observers in F1 simultaneously attach each end of the elastic band to the two rotating discs and all points of the elastic band simultaneously to the surface of the rotating clay cylinder. After the elastic band is attached that way, observers in F1 see that the elastic band is always parallel to the x-axis as it rotates about the x-axis. Observers in F0 saw that one end of the elastic band was attached and that end made 10 revolutions around the x-axis before the other end was attached. So they observe that the elastic band spirals around the clay cylinder.
Now at the point on the disc on the left where the elastic band is attached, a force is applied to pull that end of the elastic band in the negative x direction. The elastic band is pulled past this point but the point on the disc where the pulling force is applied remains at the same position on the disc. This causes the elastic band that is spiraling around the soft clay cylinder (as observed in F0) to cut into the soft clay. As the elastic band is continually pulled, the elastic band will cut through the clay until it is a straight line as observed in F0, touching the rod connecting the two discs at the midpoint between the two discs.
Please explain why observers in F1 observe that the elastic band is parallel to the x-axis before the pulling occurs, but cuts through the clay instead of remaining on the clay's surface and parallel to the x-axis as the elastic band is pulled.
Scenario 2
The setup is identical to scenario 1. But in this scenario, observers in F0 simultaneously attach both ends and all points in between of the elastic band to the discs and the rotating clay cylinder. They observe that the elastic band and all points of it are parallel to the x-axis. Observers in F1 see the elastic band spiral about the cylinder. Now when a force at the left disc where the elastic band is applied to pull the elastic band in the negative x direction observers in F0 see that the elastic band always remains on the surface of the clay cylinder. Why do observers in F1, say that the spiraling elastic band never cuts through the soft clay as this force is continually pulling on the elastic band?
Scenario 3
This scenario is similar to scenario 1 but instead of a soft clay cylinder, there is a cylinder made of ice, and there are two elastic bands just above the cylinder running parallel to the x-axis. The two elastic bands are side by side separated by 1 cm. There is no rod between the two rotating discs in this scenario.
In F1, observers attach all points of the two elastic bands simultaneously to the two rotating discs and the surface of the rotating ice cylinder. They observe that the two elastic bands are always parallel to the x-axis. Now the ice melts and disappears. Let there be a force on the two points of the left disc where the elastic bands are attached that pulls each band identically in the negative x-direction. Now the two elastic bands will eventually be observed to wrap around each other 10 times. How do observers in F1 say that two parallel bands could possibly wrap themselves around each other 10 times in this scenario?
Thanks,
David Seppala
Bastrop TX
Trevor Lange
Jan 26, 2023, 9:51:21 AM1/26/23
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On Wednesday, January 25, 2023 at 4:35:15 PM UTC-8, sep...@yahoo.com wrote:
> I posted a similar problem but no one explained things in a logical way.
That is not true. Each time you have posted this same question previously, it has been clearly and thoroughly explained, and each of your follow-up questions has been answered, and all your misconceptions have been carefully explained. If there is something about the explanation that you don't understand, go ahead and quote the specific part of the explanation that seemed unclear to you, and it can be clarified. Don't just re-type your original question, type the part of the answer that is unclear.
> I posted a similar problem but no one explained things in a logical way.
sep...@yahoo.com
Jan 26, 2023, 12:35:55 PM1/26/23
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On Thursday, January 26, 2023 at 8:51:21 AM UTC-6, Trevor Lange wrote:
> On Wednesday, January 25, 2023 at 4:35:15 PM UTC-8, sep...@yahoo.com wrote:
> > I posted a similar problem but no one explained things in a logical way.
> That is not true. Each time you have posted this same question previously, it has been clearly and thoroughly explained, and each of your follow-up questions has been answered, and all your misconceptions have been carefully explained. If there is something about the explanation that you don't understand, go ahead and quote the specific part of the explanation that seemed unclear to you, and it can be clarified. Don't just re-type your original question, type the part of the answer that is unclear.\
> On Wednesday, January 25, 2023 at 4:35:15 PM UTC-8, sep...@yahoo.com wrote:
> > I posted a similar problem but no one explained things in a logical way.
The third scenario of this post has never been addressed. Why don't you post your physics explanation?
David Seppala
Bastrop TX
Trevor Lange
Jan 26, 2023, 5:26:00 PM1/26/23
to
On Thursday, January 26, 2023 at 9:35:55 AM UTC-8, sep...@yahoo.com wrote:
> > That is not true. Each time you have posted this same question previously, it has been clearly and thoroughly explained, and each of your follow-up questions has been answered, and all your misconceptions have been carefully explained. If there is something about the explanation that you don't understand, go ahead and quote the specific part of the explanation that seemed unclear to you, and it can be clarified. Don't just re-type your original question, type the part of the answer that is unclear.
>
> The third scenario of this post has never been addressed. Why don't you post your physics explanation?
To be clear, are you saying that you fully understand the first two scenarios, and you realize they are perfecty consistent and logically irrefutable, and your ownly uncertainty pertains to your third scenario?
> > That is not true. Each time you have posted this same question previously, it has been clearly and thoroughly explained, and each of your follow-up questions has been answered, and all your misconceptions have been carefully explained. If there is something about the explanation that you don't understand, go ahead and quote the specific part of the explanation that seemed unclear to you, and it can be clarified. Don't just re-type your original question, type the part of the answer that is unclear.
>
> The third scenario of this post has never been addressed. Why don't you post your physics explanation?
This is important to know, because if you understand the first two scenarios, the third follows trivially. On the other hand, if you still don't understand the first two scenarios, that you agree have been asked and answered previously, then I say again: Quote the specific part of the explanation that seemed unclear to you, and it can be clarified. Don't just re-type your original question, type the part of the answer that is unclear.
sep...@yahoo.com
Jan 26, 2023, 6:22:14 PM1/26/23
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David Seppala
Bastrop TX
Sylvia Else
Jan 26, 2023, 6:32:42 PM1/26/23
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On 26-Jan-23 11:35 am, sep...@yahoo.com wrote:
>After the elastic band is attached that way, observers in F1 see that the elastic band is always parallel to the x-axis as it rotates about the x-axis.
This requires the band to start moving simultaneously along its length
>After the elastic band is attached that way, observers in F1 see that the elastic band is always parallel to the x-axis as it rotates about the x-axis.
in F1, but there is no reason for it to do so, since it is only attached
at its ends.
When you posit non-physical behaviour, and then seek to apply the laws
of physics to determine what follows, your conclusions will be meaningless.
Sylvia.
sep...@yahoo.com
Jan 26, 2023, 6:47:00 PM1/26/23
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In my original post I said observers in F1 simultaneously attach the two ends of the elastic band to the discs and all points in between to the surface of the soft clay cylinder. So no the elastic band is not only attached at its ends.
David Seppala
Bastrop TX
Sylvia Else
Jan 26, 2023, 7:09:01 PM1/26/23
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Sylvia.
Trevor Lange
Jan 26, 2023, 7:14:24 PM1/26/23
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On Thursday, January 26, 2023 at 3:22:14 PM UTC-8, sep...@yahoo.com wrote:
> What I don't understand is why when a force at the left disc pulls the elastic
> band in the negative direction while it is still attached to the disc on the right...
> What I don't understand is why when a force at the left disc pulls the elastic
This was all explained very clearly the last time you asked (and the time before that). Again, don't just repeat your question, quote the answer you've been given, and specify what part you think is illogical or unclear. At the conclusion of the previous thread, you conceeded that you had simply been misunderstanding things. Remember?
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