Robittybob1 Posted February 25, 2015 Posted February 25, 2015 One thing you have to realize is the the Earth's magnetic field isn't really affixed to the Earth. It doesn't even line up with the Earth's axis of rotation nor does it stay in the same place. Presently, the North Magnetic pole is some 4 degrees away from the physcial North pole, but it moves some 55-60 km every year and at the turn of the 20th century it was in Northern Canada and some 30 degrees from the North pole. If the orientation of the Earth's magnetic field had any significant effect on the the Earth's rotation rate and the length of the day, we would have noticed over the last 100 yrs or so. The Earth has been slowing its rate of rotation ever since the Moon was formed or captured. I have seen day lengths talked about as short as 5 hours originally, and now it is 24 hours and still getting longer. More energy and momentum has been lost than ever can be accounted for going to tidally accelerate the Moon (that accounts for around 20%) so in my opinion the Earth's magnetic field could account for some of the remainder. The magnetic field is a type of electromagnet from the production of a current, currents are known to have a resistance and hence heating, heating is a form of energy loss. Well mechanical energy is converted to electrical energy and heat hence slowing the rotation of the Earth.
Acme Posted February 25, 2015 Posted February 25, 2015 ... so in my opinion the Earth's magnetic field could account for some of the remainder. ... Your opinion is of no consequence.
Robittybob1 Posted February 25, 2015 Author Posted February 25, 2015 (edited) Your opinion is of no consequence. I've studied this topic so I do have opinions on the topic thanks very much. Not only that it is an opinion the physics logic is hard to refute. Argue the physics please. Edited February 25, 2015 by Robittybob1
imatfaal Posted February 25, 2015 Posted February 25, 2015 Your opinion is of no consequence. I've studied this topic so I do have opinions on the topic thanks very much. Acme's comment is a little harsh - but completely true. It is what you can PROVE that is of consequence. Where do you get your 20% from? That requires maths - so pony up the sums 2
Acme Posted February 25, 2015 Posted February 25, 2015 I've studied this topic so I do have opinions on the topic thanks very much. I know. But you know what they say about opinions. The fact is that you have not now -or never have- produced any evidence for your opinions on this topic, making those opinions inconsequential. 1
Robittybob1 Posted February 25, 2015 Author Posted February 25, 2015 I know. But you know what they say about opinions. The fact is that you have not now -or never have- produced any evidence for your opinions on this topic, making those opinions inconsequential. The science speaks for itself. The magnetic pole "flips" and it wanders but there aren't lengths of time where the magnetic pole was "sideways" so I would further opinion that it is always related to the spinning Earth (aligned) and caused by the Earth's spin. Acme's comment is a little harsh - but completely true. It is what you can PROVE that is of consequence. Where do you get your 20% from? That requires maths - so pony up the sums I read figures of that magnitude in Wikipedia on tidal acceleration of the Moon within the last few days. ( I now see I was out by a factor of ten.) Angular momentum and energy[edit]The gravitational torque between the Moon and the tidal bulge of Earth causes the Moon to be constantly promoted to a slightly higher orbit and Earth to be decelerated in its rotation. As in any physical process within an isolated system, total energy and angular momentum are conserved. Effectively, energy and angular momentum are transferred from the rotation of Earth to the orbital motion of the Moon (however, most of the energy lost by Earth (-3.321 TW) is converted to heat by frictional losses in the oceans and their interaction with the solid Earth, and only about 1/30th (+0.121 TW) is transferred to the Moon).
Acme Posted February 25, 2015 Posted February 25, 2015 The science speaks for itself. The magnetic pole "flips" and it wanders but there aren't lengths of time where the magnetic pole was "sideways" so I would further opinion that it is always related to the spinning Earth (aligned) and caused by the Earth's spin. Again and again and again; your opinion is of no consequence or merit here much less in the numerous other threads we have on Earth's and the Sun's magnetic fields in which you have opined and disregarded the factual information presented. 1
Robittybob1 Posted February 25, 2015 Author Posted February 25, 2015 Again and again and again; your opinion is of no consequence or merit here much less in the numerous other threads we have on Earth's and the Sun's magnetic fields in which you have opined and disregarded the factual information presented. Principally because what you say is factual is mere reasoned opinion of someone else. -1
Acme Posted February 25, 2015 Posted February 25, 2015 Acme's comment is a little harsh - but completely true. It is what you can PROVE that is of consequence. Where do you get your 20% from? That requires maths - so pony up the sums Are we on about science and facts or not? You took care to comment on my style of delivery and left Bobbity's ongoing trollish comments to pass. How about reiterating your comment to Bobbity until he ponies up the math, and when he doesn't comply [kindly & tenderly] tell him to stop the posting of opinions. Bunch of damn nonsense all around. To get back to the OP, in spite of peoples' feelings that the Sun's magnetic field drags on Earth's magnetic field and changes Earth's rate of rotation, there is no such evidence. I repeat [at the risk of harshitudinality], NO SUCH EVIDENCE. Moreover, because both the Sun's and Earth's magnetic polarities wander and reverse, were there any such powerful drag it too would reverse and alternately speed up and slow down Earth's rotation and there is no such evidence that this is happening or that it has happened.
Robittybob1 Posted February 25, 2015 Author Posted February 25, 2015 Are we on about science and facts or not? You took care to comment on my style of delivery and left Bobbity's ongoing trollish comments to pass. How about reiterating your comment to Bobbity until he ponies up the math, and when he doesn't comply [kindly & tenderly] tell him to stop the posting of opinions. Bunch of damn nonsense all around. To get back to the OP, in spite of peoples' feelings that the Sun's magnetic field drags on Earth's magnetic field and changes Earth's rate of rotation, there is no such evidence. I repeat [at the risk of harshitudinality], NO SUCH EVIDENCE. Moreover, because both the Sun's and Earth's magnetic polarities wander and reverse, were there any such powerful drag it too would reverse and alternately speed up and slow down Earth's rotation and there is no such evidence that this is happening or that it has happened. I never said "the Sun's magnetic field drags on Earth's magnetic field and changes Earth's rate of rotation", so where did you get that idea from? And I did answer Imatfaal with the maths. -1
Acme Posted February 25, 2015 Posted February 25, 2015 I never said "the Sun's magnetic field drags on Earth's magnetic field and changes Earth's rate of rotation", so where did you get that idea from? And I did answer Imatfaal with the maths. Your reading comprehension is abysmal. I wrote "... peoples' feelings that the Sun's magnetic field drags ...". That's "peoples'", not Blobbity's. Ant Sinclair expressed the notion early on and while not of this thread it is the similar notion expressed by Arc in his ongoing unsupported opinion on plate tectonics elsewhere. Imatfaal can respond -or not- as to whether you satisfied his demand. All-inall, your contributions to this thread are not worth the virtual ink they are keyed with and serve only to stir up the muds.
Robittybob1 Posted February 25, 2015 Author Posted February 25, 2015 (edited) Thanks Janus for Your reply, if say the Earth did swing from 23.5° to 0° would its' magnetic field follow in any way or would it stay where it was? In previous work that we had done on the Earth's magnetic field (on another forum) it was proposed that it was the Moon's tidal displacement of the Earth's Inner Core within the molten Earth's Outer Core that enabled the production of differential flows to occur in the outer core which could constitute an electrical current passing near the conductive Inner Core and hence a magnetic field could arise. I will admit no method of reversing this current was proposed so the hypothesis failed in that regard. If the model was valid and what you proposed ever did happen, provided the alignment of the Moon to the Earth's Inner Core did not change, the Earth's magnetic field with respect to the Sun would be much the same as it currently is. Your reading comprehension is abysmal. I wrote "... peoples' feelings that the Sun's magnetic field drags ...". That's "peoples'", not Blobbity's. Ant Sinclair expressed the notion early on and while not of this thread it is the similar notion expressed by Arc in his ongoing unsupported opinion on plate tectonics elsewhere. Imatfaal can respond -or not- as to whether you satisfied his demand. All-inall, your contributions to this thread are not worth the virtual ink they are keyed with and serve only to stir up the muds. That maybe so but you did not make it clear whose "feelings" you were referring to originally, so I just wanted to make it clear to everyone they did not represent my view. .... First, Earth will not 'swing' as you describe. Nonetheless, the orientation of the magnetic field is described relative to the geographic poles so IF Earth swang to zero then yes, the magnetic field orientation would follow. So if the magnetic pole were at 72.21°W longitude and 80.08°N latitude before the swing, it would be at that same location after Earth swang. That opinion is contrary to my previous posting. Edited February 25, 2015 by Robittybob1 -1
swansont Posted February 26, 2015 Posted February 26, 2015 The Earth has been slowing its rate of rotation ever since the Moon was formed or captured. I have seen day lengths talked about as short as 5 hours originally, and now it is 24 hours and still getting longer. More energy and momentum has been lost than ever can be accounted for going to tidally accelerate the Moon (that accounts for around 20%) Where's the evidence that heating can't account for the difference? The science speaks for itself. The magnetic pole "flips" and it wanders but there aren't lengths of time where the magnetic pole was "sideways" so I would further opinion that it is always related to the spinning Earth (aligned) and caused by the Earth's spin. There aren't? You have evidence that this never occurs? The science speaks for itself. The magnetic pole "flips" and it wanders but there aren't lengths of time where the magnetic pole was "sideways" so I would further opinion that it is always related to the spinning Earth (aligned) and caused by the Earth's spin. I read figures of that magnitude in Wikipedia on tidal acceleration of the Moon within the last few days. ( I now see I was out by a factor of ten.) 1/5 is not a factor of ten off from 1/30 In previous work that we had done on the Earth's magnetic field (on another forum) it was proposed that it was the Moon's tidal displacement of the Earth's Inner Core within the molten Earth's Outer Core that enabled the production of differential flows to occur in the outer core which could constitute an electrical current passing near the conductive Inner Core and hence a magnetic field could arise. Don't really care about some nonsense you posted somewhere else. I never said "the Sun's magnetic field drags on Earth's magnetic field and changes Earth's rate of rotation", so where did you get that idea from? And I did answer Imatfaal with the maths. I don't think I can fault anyone for guessing here, because your claim was rather vague. You just said the magnetic field was responsible for slowing. That leaves other to guess how that might occur, and an interaction with the sun's field is one possible mechanism to consider. And you did not answer imatfaal with maths, you quoted a number from wikipedia which in no way provides evidence for your assertion. So, the bottom line here is whether or not you have any science to present to support your claim. Do you have evidence, or a model, or anything testable/falsifiable?
Robittybob1 Posted February 26, 2015 Author Posted February 26, 2015 (edited) Where's the evidence that heating can't account for the difference? There aren't? You have evidence that this never occurs? 1/5 is not a factor of ten off from 1/30 Don't really care about some nonsense you posted somewhere else. I don't think I can fault anyone for guessing here, because your claim was rather vague. You just said the magnetic field was responsible for slowing. That leaves other to guess how that might occur, and an interaction with the sun's field is one possible mechanism to consider. And you did not answer imatfaal with maths, you quoted a number from wikipedia which in no way provides evidence for your assertion. So, the bottom line here is whether or not you have any science to present to support your claim. Do you have evidence, or a model, or anything testable/falsifiable? Did you understand what I was saying? There are many processes that result in heating of the Earth and result in the slowing the rotation of the Earth. Someone else did the calculation of the proportion of how much of the Earth's momentum and energy has gone into tidally accelerating the Moon, the figures quoted in Wikipedia are 1/30 th. (that is what we call "the maths" in NZ. Was that not enough? So to me 1/30th is a factor of ten out (one order of magnitude), from my poorish recollection of 20%. OK I realise 1/3 and 1/30th is more exact but I wasn't talking about being exactly correct but "order of magnitude". Wikipedia talks about the energy lost. Momentum loss is another figure as well. (I should stop say "energy and momentum is lost" for the amounts are different.) (however, most of the energy lost by Earth (-3.321 TW) is converted to heat by frictional losses in the oceans and their interaction with the solid Earth, and only about 1/30th (+0.121 TW) is transferred to the Moon) So if there is a "dynamo effect" in the Outer Core that process will take energy and the result is heat plus the magnetic field. So heating does account for the difference, but what is causing that heating? Well in all my reading about the topic I have never read about "sideways magnetic alignments" (allowing for a degree of wandering of course), but my understanding was that it was a more total reversal at various stages in history on a fairly irregular pattern as opposed to the Sun which is on the 22 year cycle. (Now if my ideas on this are wrong I will stand correction. OK the reversal takes time so what happens during a pole shift is not that clear. Is there a short period of sideways magnetic alignment? Do you know?) I think there is plenty of evidence that an electromagnet will produce heating. What other parts did you need proof of? Edited February 26, 2015 by Robittybob1
swansont Posted February 27, 2015 Posted February 27, 2015 Did you understand what I was saying? There are many processes that result in heating of the Earth and result in the slowing the rotation of the Earth. Someone else did the calculation of the proportion of how much of the Earth's momentum and energy has gone into tidally accelerating the Moon, the figures quoted in Wikipedia are 1/30 th. (that is what we call "the maths" in NZ. Was that not enough? So to me 1/30th is a factor of ten out (one order of magnitude), from my poorish recollection of 20%. OK I realise 1/3 and 1/30th is more exact but I wasn't talking about being exactly correct but "order of magnitude". Wikipedia talks about the energy lost. Momentum loss is another figure as well. (I should stop say "energy and momentum is lost" for the amounts are different.) So if there is a "dynamo effect" in the Outer Core that process will take energy and the result is heat plus the magnetic field. So heating does account for the difference, but what is causing that heating? The friction involved in the tides. Slosh water around, and it heats up a little. The solid earth undergoes tidal movement as well. Only about a third as large as with water, because the earth is not as deformable. There's going to be a considerable amount of friction involved in bending the earth's surface by a few tens of cm. Well in all my reading about the topic I have never read about "sideways magnetic alignments" (allowing for a degree of wandering of course), but my understanding was that it was a more total reversal at various stages in history on a fairly irregular pattern as opposed to the Sun which is on the 22 year cycle. (Now if my ideas on this are wrong I will stand correction. OK the reversal takes time so what happens during a pole shift is not that clear. Is there a short period of sideways magnetic alignment? Do you know?) I don't, but you are the one who made the claim, implying that you do know. I think there is plenty of evidence that an electromagnet will produce heating. What other parts did you need proof of? That's a failure of basic logic. All electromagnets produce heating, but not all heating is the result of electromagnets. Universal affirmatives can only be partially converted.
Robittybob1 Posted February 27, 2015 Author Posted February 27, 2015 The friction involved in the tides. Slosh water around, and it heats up a little. The solid earth undergoes tidal movement as well. Only about a third as large as with water, because the earth is not as deformable. There's going to be a considerable amount of friction involved in bending the earth's surface by a few tens of cm. I don't, but you are the one who made the claim, implying that you do know. That's a failure of basic logic. All electromagnets produce heating, but not all heating is the result of electromagnets. Universal affirmatives can only be partially converted. I agree, not all the heating is produced by the Earth's electromagnetic field production; I have never ever attempted to say it was, so we agree on that point (I think, but you can confirm that). So do we agree a proportion of the Earth's internal heating is the result of electrical resistance? (for it is current going through a resistor that produces heat), and what causes the current to flow is debatable. Whether it is the coriolis effect or the displacement of the Earth's inner core, nevertheless both methods are going to act as a brake on the Earth's rotation. The only claim was that I haven't read about a "sideways magnetic field" during times of magnetic pole reversal. From memory it is more a fading out and then resuming in the opposite polarity, yet I have not been really convinced about how that happens.
swansont Posted February 27, 2015 Posted February 27, 2015 I agree, not all the heating is produced by the Earth's electromagnetic field production; I have never ever attempted to say it was, so we agree on that point (I think, but you can confirm that). Yes, you did, in the OP. "More energy and momentum has been lost than ever can be accounted for going to tidally accelerate the Moon (that accounts for around 20%) so in my opinion the Earth's magnetic field could account for some of the remainder." That's the point of contention. Do you have any actual physics to show that this is true?
Robittybob1 Posted February 27, 2015 Author Posted February 27, 2015 (edited) Yes, you did, in the OP. "More energy and momentum has been lost than ever can be accounted for going to tidally accelerate the Moon (that accounts for around 20%) so in my opinion the Earth's magnetic field could account for some of the remainder." That's the point of contention. Do you have any actual physics to show that this is true? Are we debating how much "some of the remainder" is? I re-read my original post on the topic and to me I make it clear it is the production of the electrical current that causes both the magnetic field and some heating (current going through a resistance). That is fairly standard physics isn't it. Electrical currents will produce heat. Last year I tried to find out how much current would be required to produce a magnetic field the size of the Earth's and there are estimates but I'm not strong on understanding the figures that have been estimated. Edit: I have no actual conception of what proportion of that heating is due to the electrical current. But if it was really important I could try and look into it again. Edited February 27, 2015 by Robittybob1
swansont Posted February 27, 2015 Posted February 27, 2015 I have no actual conception of what proportion of that heating is due to the electrical current. And, presumably, if any of this is connected to the slowdown in the rotation rate of the earth.
Robittybob1 Posted February 27, 2015 Author Posted February 27, 2015 (edited) And, presumably, if any of this is connected to the slowdown in the rotation rate of the earth. As kids we had these things called "dynamos" to power the lights on your bicycle. It rubbed on the tire and if the light was working you had to pedal real hard to make it turn fast enough to produce enough light. So when I read about the dynamo in the center of the Earth I can't but help thinking it is going to need something to keep it rotating, and the other part stationary (the housing of the dynamo as they wouldn't work if they were loosely mounted). https://www.youtube.com/watch?v=9MFWlwtwEN8 There are a couple of badly mounted dynamos in this clip. It should not be contacting the steel rim for a starter. Edited February 27, 2015 by Robittybob1
Endy0816 Posted February 27, 2015 Posted February 27, 2015 What would happen if you set the bike sideways, then spun both the wheel and the bike around the wheel hub at different rates?
swansont Posted February 27, 2015 Posted February 27, 2015 A generator requires that you do work because you are converting that energy to another form; in this case lighting a fairly inefficient light bulb. The dynamo in the earth is creating a magnetic field, but there's no other half to that — there's no output. So the analogy doesn't really work.
Robittybob1 Posted February 27, 2015 Author Posted February 27, 2015 (edited) What would happen if you set the bike sideways, then spun both the wheel and the bike around the wheel hub at different rates? You get skinned knees every time for sure. A generator requires that you do work because you are converting that energy to another form; in this case lighting a fairly inefficient light bulb. The dynamo in the earth is creating a magnetic field, but there's no other half to that — there's no output. So the analogy doesn't really work. Bicycle generators worked off permanent magnets but unlike the Earth, the Earth is not a permanent magnet, it is an electromagnet, and that is an output on its own. Edited February 27, 2015 by Robittybob1
swansont Posted February 27, 2015 Posted February 27, 2015 Bicycle generators worked off permanent magnets but unlike the Earth, the Earth is not a permanent magnet, it is an electromagnet, and that is an output on its own. And? If you move some charges you will create a magnetic field. Where is the energy loss?
Robittybob1 Posted February 27, 2015 Author Posted February 27, 2015 (edited) And? If you move some charges you will create a magnetic field. Where is the energy loss? Was it Ohm's law? No that was V=I*R. From Wikipedia on electrical resistance: The formula for Joule heating is:P = I^2 * R where P is the power (energy per unit time) converted from electrical energy to thermal energy, R is the resistance, and I is the current through the resistor. It is going to take work to move those electrical charges (and how do you make the fluids electrically charged in the first place?) With molten metal you are going to have equal numbers of electrons and protons so when you move it, is that a current? To me that seems to be a two way current and the magnetic effects were going to cancel. You are also going to have to have a way of making them move faster than their metal surroundings. What is going to make those charges move? Edited February 27, 2015 by Robittybob1
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