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Let there is a triplet of A, B, and C on an asteroid initially. A stays on an asteroid while B and C set out for a long space journey with high speed (say 0.5c and 0.9c) at the same time in the same direction relative to A. Assume each 10 years old at the time of departure. B and C are gone for 60 years relative to A. Afterward, B and C return home at the same time and reunited with A on an asteroid.
What would be the age of A relative to B and C?
What would be the age of B relative to C and A?
What would be the age of C relative to A and B?
Since each person can have only one physical appearance and one age. Thus who would be right? 2001:56A:739C:6D00:D418:247C:CE19:4D81 ( talk) 03:07, 23 October 2016 (UTC)eek
I didn’t include many things in order to keep the question short as i presumed that it was understandable from pundits pov. Since everything is ideal / theoritical therefore B and C are also traveling in the ideal rocket ship. Their rocket ships can accelerate up to their desired speed within second or minute in the time frame of A. Further they can stop just for a movement and come back through the same route - no turn around.So I think acceleration or declaration ( two or three seconds / minutes) should not be the problem while calculating the ages. Regarding “Right”
1. B and C have disagreement on the age as well as physical appearance of A
2. A and B have disagreement on the age as well as physical appearance of C
3. C and A have disagreement on the age as well as physical appearance of B
Although we can add infinite number of clowns of the aforementioned leader to the scenario but for simplicity, 96 clowns are sufficient to understand if it is difficult to guess who is right on the age as well as the physical appearance of A, B and C. Clown# 96 stays on an asteroid while the rest take off at the same time with the following speeds relative to Clown#96, in the same direction for their long synchronized space journey. Assume each 10 years old at the time of departure. All 95 clowns gone for 90 years relative to clown 96. Afterward, 1 to 95 return home at the same time and reunited with clown 96 on an asteroid.
Speed of clown 1 is 0.01c , 2 is 0.02c, 3 is 0.03c, 4 is 0.04 c, ..., 10 is 0.1c, ......, 20 is 0.2c, ......, 90 is 0.9c, ....,95 is 0.95c
Again: One clown can have only one age and one physical appearance therefore who would be right on the age as well as the physical appearance of 96 clowns.
Make the above triplet paradox quadruple
Our solar system revolves around another celestial mass of our galaxy. Assume D the fourth brother / sister of aforementioned A, B and C is on this celestial mass. Since D experienced no time dilation so D finds B and C aged at the same rate as A via his special binocular. D is in disagreement with A, B, and C. 2001:56A:739C:6D00:D77:CB3B:5A2B:EBDD ( talk) 03:51, 24 October 2016 (UTC)eek
Thank you AllBestFaith for correcting me. My mind is very scattered nowadays due to some inexplicable reasons, therefore, I apologize for the mistake. Further, doesn’t space dilate for moving frames instead of time? 2001:56A:739C:6D00:E867:777:70B1:58FF ( talk) 02:12, 25 October 2016 (UTC)Eclectic Eccentric kamikaze
The word time dilation in a sentence itself explains that observations are made from different inertial frames. Since time dilation is the main crux of the discussion so it’s not necessary to mention inertial frames all the time impov.
There seem to be many attempts at redefining the value of the kilogram, especially since it remained the only SI unit still dependable upon a physical artifact. Are there any practical reasons for trying to (re)define the kilogram in terms of atmospheric pressure, or height of column of mercury under specific temperature and gravity conditions (such as, for instance, [re]defining the pressure exercised by a column of mercury 3⁄4 m tall at 0°C and standard gravity as 105 N exactly) ? I ask this because I don't know how practically feasible it would be to extract mass from pressure, rather than the other way around. — 79.113.203.205 ( talk) 04:23, 23 October 2016 (UTC)
Defining the kilogramme in terms of pressure is actually a fairly good idea, as I see it; the trick is not to use atmospheric pressure (which, as has been noted above numerous times, highly variable), but rather some pressure the value of which is completely invariant, such as the pressure at the triple point of a pure substance, or the critical pressure of a pure substance. For instance, the vapour–He-I–He-II triple point of helium-4 (which is actually one of four triple points for 4He—see the table in triple point) has a pressure of 5.048 kilopascals (0.04982 atmospheres); if one set the pressure for this triple point at exactly 5.048 kPa, one could then define the newton in terms of the pascal and the metre, and, then, in turn, define the kilogramme in terms of the newton, the metre, and the second, totally eliminating the need for the International Prototype Kilogramme, which could then be consigned to a museum as a historical artifact, just like the International Prototype Metre has been. Or, if one desired, one could take the critical pressure of oxygen (5.043 megapascals), define it as exactly 5.043 MPa, and use that to define the newton, and, by extension, the kilogramme. Whoop whoop pull up Bitching Betty | Averted crashes 16:02, 23 October 2016 (UTC)
I don't understand why does Feynman set aside reflected wave, deriving the formula. He says "since the two amplitudes on the left side of Eq. (33.2) each produce the wave of amplitude −1.". Even geometrically it is not true
PNG
dwg.
Formula must be next:
Username160611000000 ( talk) 12:22, 23 October 2016 (UTC)
Later Feynman says :
Quote
It is possible to go on with arguments of this nature and deduce that b is real. To prove this, one must consider a case where light is coming from both sides of the glass surface at the same time, a situation not easy to arrange experimentally, but fun to analyze theoretically. If we analyze this general case, we can prove that b must be real, and therefore, in fact, that b=±sin(i−r)/sin(i+r). It is even possible to determine the sign by considering the case of a very, very thin layer in which there is reflection from the front and from the back surfaces, and calculating how much light is reflected. We know how much light should be reflected by a thin layer, because we know how much current is generated, and we have even worked out the fields produced by such currents.
Unquote
I do not recall that Feynman ever showed the formula for current. It seems he uses
31.17 to show that field which is generated by glass has inverse sign of source field. But I can't understand why should we use a case when light is reflected from both sides of the glass plate? And second, why should we prove that is real value? is real.
Username160611000000 ( talk) 17:51, 23 October 2016 (UTC)
Earth ocean rifts total gas output
Is there a source that provides Earth's ocean rifts total gas outputs to the oceans and to Earth's atmosphere? Terry D Welander ( talk) 18:35, 23 October 2016 (UTC) [Redacted] — Preceding unsigned comment added by 173.21.166.135 ( talk) 18:22, 23 October 2016 (UTC)
If the Americas were pushed out to sea about how fast would the land have to move to repeat (more or less) Hurricane Sandy's surge in New York Harbor? With several minutes of acceleration time. How long would it take the new sea level to reach equilibrium? Would a few minutes acceleration time be enough for it to be more like a surge than a tsunami? Yes, yes the power to cut a continent off the Earth and move it and keep it from sinking or causing earthquakes is beyond ludicrous. I just wonder about the wrong frame of reference where the land moves instead of the water. Sagittarian Milky Way ( talk) 19:15, 23 October 2016 (UTC)
Does anyone happen to know what is the peak G-force that the Orion Spaceship experiences during launch and/or atmospheric reentry? 2601:646:8E01:7E0B:40E5:EEF0:65B8:D229 ( talk) 23:14, 23 October 2016 (UTC)
So it's been established that a five-ounce bird cannot carry a one-pound coconut. But are there any aircraft (non-experimental) that can carry at this ratio, with the maximum safe weight of cargo being more than three times the manufacturer's empty weight? I note that two prominent US military cargo aircraft, the Lockheed C-5 Galaxy and the Lockheed C-130 Hercules, both have manufacturer's empty weights that are greater than their cargo capacities, so I'm guessing that any such aircraft would be much smaller, since the USAF might well not use their current aircraft if smaller aircraft existed that could carry similar amounts of freight or if similarly sized aircraft could carry much greater amounts of freight. Nyttend ( talk) 23:41, 23 October 2016 (UTC)
entire weight of aircraft at maximum safe load
divided by manufacturer's empty weight
is at least 3, so I was imagining an out-of-fuel aircraft for the first one. My idea was either a fixed-wing aircraft or a helicopter (but at least in my imagination, they don't carry as much weight for their size; their advantage is maneouvreability, not mere carrying capacity) flying in the atmosphere; I wondered about a space rocket, but in the end I was only thinking about atmosphere-restricted aircraft. I've never heard of rocket airplanes (except experimental ones), but if any rocket airplanes have ever gotten out of the experimental stage and become "normal" aircraft, they'd definitely be eligible for what I was looking for.
Nyttend (
talk) 01:16, 24 October 2016 (UTC)
Science desk | ||
---|---|---|
< October 22 | << Sep | October | Nov >> | October 24 > |
Welcome to the Wikipedia Science Reference Desk Archives |
---|
The page you are currently viewing is an archive page. While you can leave answers for any questions shown below, please ask new questions on one of the current reference desk pages. |
Let there is a triplet of A, B, and C on an asteroid initially. A stays on an asteroid while B and C set out for a long space journey with high speed (say 0.5c and 0.9c) at the same time in the same direction relative to A. Assume each 10 years old at the time of departure. B and C are gone for 60 years relative to A. Afterward, B and C return home at the same time and reunited with A on an asteroid.
What would be the age of A relative to B and C?
What would be the age of B relative to C and A?
What would be the age of C relative to A and B?
Since each person can have only one physical appearance and one age. Thus who would be right? 2001:56A:739C:6D00:D418:247C:CE19:4D81 ( talk) 03:07, 23 October 2016 (UTC)eek
I didn’t include many things in order to keep the question short as i presumed that it was understandable from pundits pov. Since everything is ideal / theoritical therefore B and C are also traveling in the ideal rocket ship. Their rocket ships can accelerate up to their desired speed within second or minute in the time frame of A. Further they can stop just for a movement and come back through the same route - no turn around.So I think acceleration or declaration ( two or three seconds / minutes) should not be the problem while calculating the ages. Regarding “Right”
1. B and C have disagreement on the age as well as physical appearance of A
2. A and B have disagreement on the age as well as physical appearance of C
3. C and A have disagreement on the age as well as physical appearance of B
Although we can add infinite number of clowns of the aforementioned leader to the scenario but for simplicity, 96 clowns are sufficient to understand if it is difficult to guess who is right on the age as well as the physical appearance of A, B and C. Clown# 96 stays on an asteroid while the rest take off at the same time with the following speeds relative to Clown#96, in the same direction for their long synchronized space journey. Assume each 10 years old at the time of departure. All 95 clowns gone for 90 years relative to clown 96. Afterward, 1 to 95 return home at the same time and reunited with clown 96 on an asteroid.
Speed of clown 1 is 0.01c , 2 is 0.02c, 3 is 0.03c, 4 is 0.04 c, ..., 10 is 0.1c, ......, 20 is 0.2c, ......, 90 is 0.9c, ....,95 is 0.95c
Again: One clown can have only one age and one physical appearance therefore who would be right on the age as well as the physical appearance of 96 clowns.
Make the above triplet paradox quadruple
Our solar system revolves around another celestial mass of our galaxy. Assume D the fourth brother / sister of aforementioned A, B and C is on this celestial mass. Since D experienced no time dilation so D finds B and C aged at the same rate as A via his special binocular. D is in disagreement with A, B, and C. 2001:56A:739C:6D00:D77:CB3B:5A2B:EBDD ( talk) 03:51, 24 October 2016 (UTC)eek
Thank you AllBestFaith for correcting me. My mind is very scattered nowadays due to some inexplicable reasons, therefore, I apologize for the mistake. Further, doesn’t space dilate for moving frames instead of time? 2001:56A:739C:6D00:E867:777:70B1:58FF ( talk) 02:12, 25 October 2016 (UTC)Eclectic Eccentric kamikaze
The word time dilation in a sentence itself explains that observations are made from different inertial frames. Since time dilation is the main crux of the discussion so it’s not necessary to mention inertial frames all the time impov.
There seem to be many attempts at redefining the value of the kilogram, especially since it remained the only SI unit still dependable upon a physical artifact. Are there any practical reasons for trying to (re)define the kilogram in terms of atmospheric pressure, or height of column of mercury under specific temperature and gravity conditions (such as, for instance, [re]defining the pressure exercised by a column of mercury 3⁄4 m tall at 0°C and standard gravity as 105 N exactly) ? I ask this because I don't know how practically feasible it would be to extract mass from pressure, rather than the other way around. — 79.113.203.205 ( talk) 04:23, 23 October 2016 (UTC)
Defining the kilogramme in terms of pressure is actually a fairly good idea, as I see it; the trick is not to use atmospheric pressure (which, as has been noted above numerous times, highly variable), but rather some pressure the value of which is completely invariant, such as the pressure at the triple point of a pure substance, or the critical pressure of a pure substance. For instance, the vapour–He-I–He-II triple point of helium-4 (which is actually one of four triple points for 4He—see the table in triple point) has a pressure of 5.048 kilopascals (0.04982 atmospheres); if one set the pressure for this triple point at exactly 5.048 kPa, one could then define the newton in terms of the pascal and the metre, and, then, in turn, define the kilogramme in terms of the newton, the metre, and the second, totally eliminating the need for the International Prototype Kilogramme, which could then be consigned to a museum as a historical artifact, just like the International Prototype Metre has been. Or, if one desired, one could take the critical pressure of oxygen (5.043 megapascals), define it as exactly 5.043 MPa, and use that to define the newton, and, by extension, the kilogramme. Whoop whoop pull up Bitching Betty | Averted crashes 16:02, 23 October 2016 (UTC)
I don't understand why does Feynman set aside reflected wave, deriving the formula. He says "since the two amplitudes on the left side of Eq. (33.2) each produce the wave of amplitude −1.". Even geometrically it is not true
PNG
dwg.
Formula must be next:
Username160611000000 ( talk) 12:22, 23 October 2016 (UTC)
Later Feynman says :
Quote
It is possible to go on with arguments of this nature and deduce that b is real. To prove this, one must consider a case where light is coming from both sides of the glass surface at the same time, a situation not easy to arrange experimentally, but fun to analyze theoretically. If we analyze this general case, we can prove that b must be real, and therefore, in fact, that b=±sin(i−r)/sin(i+r). It is even possible to determine the sign by considering the case of a very, very thin layer in which there is reflection from the front and from the back surfaces, and calculating how much light is reflected. We know how much light should be reflected by a thin layer, because we know how much current is generated, and we have even worked out the fields produced by such currents.
Unquote
I do not recall that Feynman ever showed the formula for current. It seems he uses
31.17 to show that field which is generated by glass has inverse sign of source field. But I can't understand why should we use a case when light is reflected from both sides of the glass plate? And second, why should we prove that is real value? is real.
Username160611000000 ( talk) 17:51, 23 October 2016 (UTC)
Earth ocean rifts total gas output
Is there a source that provides Earth's ocean rifts total gas outputs to the oceans and to Earth's atmosphere? Terry D Welander ( talk) 18:35, 23 October 2016 (UTC) [Redacted] — Preceding unsigned comment added by 173.21.166.135 ( talk) 18:22, 23 October 2016 (UTC)
If the Americas were pushed out to sea about how fast would the land have to move to repeat (more or less) Hurricane Sandy's surge in New York Harbor? With several minutes of acceleration time. How long would it take the new sea level to reach equilibrium? Would a few minutes acceleration time be enough for it to be more like a surge than a tsunami? Yes, yes the power to cut a continent off the Earth and move it and keep it from sinking or causing earthquakes is beyond ludicrous. I just wonder about the wrong frame of reference where the land moves instead of the water. Sagittarian Milky Way ( talk) 19:15, 23 October 2016 (UTC)
Does anyone happen to know what is the peak G-force that the Orion Spaceship experiences during launch and/or atmospheric reentry? 2601:646:8E01:7E0B:40E5:EEF0:65B8:D229 ( talk) 23:14, 23 October 2016 (UTC)
So it's been established that a five-ounce bird cannot carry a one-pound coconut. But are there any aircraft (non-experimental) that can carry at this ratio, with the maximum safe weight of cargo being more than three times the manufacturer's empty weight? I note that two prominent US military cargo aircraft, the Lockheed C-5 Galaxy and the Lockheed C-130 Hercules, both have manufacturer's empty weights that are greater than their cargo capacities, so I'm guessing that any such aircraft would be much smaller, since the USAF might well not use their current aircraft if smaller aircraft existed that could carry similar amounts of freight or if similarly sized aircraft could carry much greater amounts of freight. Nyttend ( talk) 23:41, 23 October 2016 (UTC)
entire weight of aircraft at maximum safe load
divided by manufacturer's empty weight
is at least 3, so I was imagining an out-of-fuel aircraft for the first one. My idea was either a fixed-wing aircraft or a helicopter (but at least in my imagination, they don't carry as much weight for their size; their advantage is maneouvreability, not mere carrying capacity) flying in the atmosphere; I wondered about a space rocket, but in the end I was only thinking about atmosphere-restricted aircraft. I've never heard of rocket airplanes (except experimental ones), but if any rocket airplanes have ever gotten out of the experimental stage and become "normal" aircraft, they'd definitely be eligible for what I was looking for.
Nyttend (
talk) 01:16, 24 October 2016 (UTC)