John Cuthber Posted May 20, 2014 Posted May 20, 2014 just look at the table in this page for length of the solar day in several months of the year . the day is either longer or shorter by a few seconds, and that means the angular velocity changes as well http://en.wikipedia.org/wiki/Solar_day No it does not mean that the angular velocity of the earth changes. It means that the sun is moving relative to us, but we knew that anyway. Incidentally, if the angular velocity of the earth changes, how do geostationary satellites work? There are other issues, but until you answer that question you don't have a "theory" so I suggest you offer a nice clear explanation in your next post.
yahya515 Posted May 20, 2014 Author Posted May 20, 2014 It means that the sun is moving relative to us, but we knew that anyway. if so, why it happens at particular months of the year ? why the length is shorter and then longer and then shorter again , isn't that because of the rotation of the earth around the sun? and also the period between March and June are three Months, a quarter of the year, the earth goes from the longest radius in March to the shortest radius in June which is a quarter of the year.
John Cuthber Posted May 20, 2014 Posted May 20, 2014 The sun moves across the sky (from our point of view) It moves quicker at some times than at others because we are nearer to it at some times than at others. If you try to measure our speed by reference to the (moving) sun, you get complicated answers which depend on the month. Now you seem to have missed this bit, which is a pity because it's important. If the angular velocity of the earth changes, how do geostationary satellites work?There are other issues, but until you answer that question you don't have a "theory" so I suggest you offer a nice clear explanation in your next post.
yahya515 Posted May 20, 2014 Author Posted May 20, 2014 (edited) Incidentally, if the angular velocity of the earth changes, how do geostationary satellites work? they are not more than 30 seconds the earth goes around its axis 2*pi / 86400 =0.0000727 rad/s, in 30 seconds more to the length of the day the angular velocity will decrease to 2*pi/86430= 0.0000726 rad/s it will change positin by: 0.0000726/0.0000727=0.9986 ,2*pi =6.2831, 2*pi *0.9986 =6.2743 , 6.2831-6.2743 =0.0087 radinas , which means the satellite and the earth are away from each other in position by 0.0087 radians = 0.49 degrees and that will not affect the position of the geostationary satellite. Edited May 20, 2014 by yahya515
Ophiolite Posted May 20, 2014 Posted May 20, 2014 John, the geostationary satellites are a red-herring. They drift off position naturally and have thrusters to keep them more or less on station.
John Cuthber Posted May 20, 2014 Posted May 20, 2014 (edited) Ophiolite, Yes, there are drifts that need to be accounted for, but Yahya is predicting a significant regular pattern, that should stand out in the data quite clearly. OK,the satellite is about 35,786 kilometres away Think about pointing a dish at the satellite. your figure of 0.9986 implies that the "error" (the difference from exactly 1) is about 0.14% So the error in pointing the dish will be about 0.14% of the circumference of the orbit. That circumference is about 112000 km and 0.14% of that is 157 km. So the beam will miss the satellite by about 160km. Now, I know that the beam divergence will help a bit but that's still a detectable effect. People who do that sort of thing would notice. Why do you think they have not done so? Also, these people measure the rotation of the earth. It's their job, and they are very good at it. http://lupus.gsfc.nasa.gov/ Would you like to explain why they are getting it wrong (or perhaps you think they are lying)? So, you now need to explain how geostationary satellites work, even though the signal would miss them by a hundred miles, and you also need to explain how come NASA keep getting the wrong answer. Edited May 20, 2014 by John Cuthber
yahya515 Posted May 21, 2014 Author Posted May 21, 2014 they are not more than 30 seconds the earth goes around its axis 2*pi / 86400 =0.0000727 rad/s, in 30 seconds more to the length of the day the angular velocity will decrease to 2*pi/86430= 0.0000726 rad/s it will change positin by: 0.0000726/0.0000727=0.9986 ,2*pi =6.2831, 2*pi *0.9986 =6.2743 , 6.2831-6.2743 =0.0087 radinas , which means the satellite and the earth are away from each other in position by 0.0087 radians = 0.49 degrees and that will not affect the position of the geostationary satellite. I made a mistake here it is: 0.00007272/0.00007269 =0.9996 for one day the satellite will miss the earth in position by : 2*pi- 0.9996*2*pi= 0.002 radians = 0.14 degrees, during about 10 days it will miss by less than 14 degrees because the angular velocity itself is changing continuously. the angular acceleration is : during 49 days from 3rd November to 22th December the angular acceleration is (if it is constant): .00007269-0.00007272/ (49*24*60*60)= -7* (10 to the power -15) rad/s*s in 10 days the angular velocity decreases from 0.00007272 rad/s to 0.00007271 rad/s , 00.00007271/0.00007272 =0.9999 2*pi- 0.9999*2*pi =0.0006 radians =0.036 degreees , for 10 days the position wil change by 0.36 degrees, and if what Ophiolite said is right this will solve the problem your figure of 0.9986 implies that the "error" (the difference from exactly 1) is about 0.14% So the error in pointing the dish will be about 0.14% of the circumference of the orbit. That circumference is about 112000 km and 0.14% of that is 157 km. So the beam will miss the satellite by about 160km. it is not a matter of the number of kilometers, it is a matter of the angle by which the dish is pointed.
swansont Posted May 21, 2014 Posted May 21, 2014 Also, these people measure the rotation of the earth. It's their job, and they are very good at it. http://lupus.gsfc.nasa.gov/ Would you like to explain why they are getting it wrong (or perhaps you think they are lying)? There is also the Earth Orientation group, just down the hall from me at work. You have to know which way the earth is pointing so that satellite positions are known in reference to the earth, otherwise GPS has larger errors. Their polar measurements are in arcseconds, and the rotational excess length of day (i.e. related to angular speed) in milliseconds http://maia.usno.navy.mil/whatiseop.html it is not a matter of the number of kilometers, it is a matter of the angle by which the dish is pointed. But nobody is seeing this error. The empirical data say you are wrong. Did you not read the link I gave about the equation of time? The length of day variation is well understood and only a minuscule amount is due to rotational speed variation.
yahya515 Posted May 21, 2014 Author Posted May 21, 2014 But nobody is seeing this error. The empirical data say you are wrong. Did you not read the link I gave about the equation of time? The length of day variation is well understood and only a minuscule amount is due to rotational speed variation. Ok, I understand, the solar day is different from the actual rotation period of earth, but I still claim that the change in the earth velocity or its radius or both will lead to change in its rotational speed, and that if the ratio (v/r) is not constant.
swansont Posted May 21, 2014 Posted May 21, 2014 Ok, I understand, the solar day is different from the actual rotation period of earth, but I still claim that the change in the earth velocity or its radius or both will lead to change in its rotational speed, and that if the ratio (v/r) is not constant. IOW you claim something will happen, there is no evidence of this happening, yet you still claim it happens.
John Cuthber Posted May 22, 2014 Posted May 22, 2014 it is not a matter of the number of kilometers, it is a matter of the angle by which the dish is pointed. Do you really not understand that those are the same thing? If I point the dish in the wrong direction by some angle, it will miss the satellite by some distance. You can calculate one from the other.
yahya515 Posted May 25, 2014 Author Posted May 25, 2014 Do you really not understand that those are the same thing? If I point the dish in the wrong direction by some angle, it will miss the satellite by some distance. You can calculate one from the other. they are the same, but the measurement is by the angle, the directin of the dish is measured by the angle. IOW you claim something will happen, there is no evidence of this happening, yet you still claim it happens. may you explain please why when I hang an object by a string and I rotate around the object will rotate around its axis at a particular dirction and when I increase the speed it rotates faster.
arc Posted May 25, 2014 Posted May 25, 2014 may you explain please why when I hang an object by a string and I rotate around the object will rotate around its axis at a particular dirction and when I increase the speed it rotates faster. yahya, I think your testing apparatus is giving you a false reading. Could you try using a shallow pan of water on your turntable instead. At the center of the pan place a small magnet. You can get one off the back of an old radio speaker. Now you need a float, get a cork or any material that would float, even a ball would work. Next, with a small nail attach a small piece of steel to the float. The metal must not be too heavy. The float material must stay above the water's surface. Now carefully add some water and test the float material above the magnet. The water must be just deep enough to allow the float to be held in place by the magnetic field's attraction but not touch the magnet or the pans bottom or sides. Now you can test your idea. Slowly rotate the pan and see if the float moves with it. Now take the magnet out and try the experiment again. Do each one multiple times and see if the magnet is applying torque like the string probably was in your original experiment. It may or may not affect these new results, but having two different sets of observations will help you to see what is affecting your data. This should help you see what forces are at play in this experiment. yahya, you haven't tried an experiment using a different apparatus, you have nothing to compare your first experimental results against. What if your string is causing the rotation to be transferred from your turntable to your object hanging by the string. You need several different ways to test your idea. The more ways you can test it the more accurate your results will be.
John Cuthber Posted May 25, 2014 Posted May 25, 2014 they are the same, but the measurement is by the angle, the directin of the dish is measured by the angle. And the point I made was that the direction of the dish is such that it misses the satellite by a hundred miles. Seriously, do you think it matters if you specify the angle by which it misses or the distance by which it misses? The problem you have is to explain why that effect has never been noticed. Can you do that?
yahya515 Posted May 25, 2014 Author Posted May 25, 2014 yahya, you haven't tried an experiment using a different apparatus, you have nothing to compare your first experimental results against. What if your string is causing the rotation to be transferred from your turntable to your object hanging by the string. You need several different ways to test your idea. The more ways you can test it the more accurate your results will be. I tried the alternative experiment with a cork of bottle but wide one, I put inside it a circular piece of iron,I put the the cork on a bowel of water, when the cork floats, I put a magnet under the cork , it attracts the iron so that the cork is at a steady position on water, when I rotated the bowel clockwise the cork started to spin counterclockwise but slowly, when I reversed the direction of rotation the cork spinned clockwise. And the point I made was that the direction of the dish is such that it misses the satellite by a hundred miles. Seriously, do you think it matters if you specify the angle by which it misses or the distance by which it misses? if you say to a person the distance betwwen Khartoum and cairo is 1800000 meters , he will need to do more calculations by dividing by 1000 to obtain 1800 km to understand clearly, the same , if you say the satellite will miss by for instance 157 km a person will need to know the distance from the earth centre to the satellite and calculate the angle in which the satellite will miss the dish at a particular place on earth, in order to redirect his reciever dish by this angle to recatch channel signals, measurements should not involve more calculations.
John Cuthber Posted May 25, 2014 Posted May 25, 2014 if you say to a person the distance betwwen Khartoum and cairo is 1800000 meters , he will need to do more calculations by dividing by 1000 to obtain 1800 km to understand clearly, the same , if you say the satellite will miss by for instance 157 km a person will need to know the distance from the earth centre to the satellite and calculate the angle in which the satellite will miss the dish at a particular place on earth, in order to redirect his reciever dish by this angle to recatch channel signals, measurements should not involve more calculations. Perhaps I have not made myself clear here. I am talking about sending the beam to the satellite. I'm not talking about the beam that comes back to the people watching television or whatever. They send that signal from a dish. If that dish is not pointing at the satellite then the signal will not reach it. The reason they use geostationary satellites is that they are always in the same "place" in the sky. But if,as you claim, the earth speeds up and slows down then the dish will not point at the satellite any more. It will miss by about a hundred miles. Once I have told you that the beam will miss by a hundred miles, what calculation do you need to do to understand that the beam will miss by a hundred miles? People would notice if the beam missed the satellite by a hundred miles because the system wouldn't work. It works, so the beam must continue to point at the satellite. But you say that the dish should move faster on some days than others. If it did that they would need to realign the dish. They don't. So, you are wrong. And you still don't seem to have answered the questions about the people who measure the Earth's rotation. Why don't they see this effect you claim? Do you understand that if the facts don't agree with your ideas then you should change your ideas? Reality does not make mistakes.
rktpro Posted May 25, 2014 Posted May 25, 2014 "may you explain please why when I hang an object by a string and I rotate around the object will rotate around its axis at a particular dirction and when I increase the speed it rotates faster." Did you read my last post? I just explained that. "may you explain please why when I hang an object by a string and I rotate around the object will rotate around its axis at a particular dirction and when I increase the speed it rotates faster." Did you read my last post? I just explained that.
arc Posted May 25, 2014 Posted May 25, 2014 (edited) I tried the alternative experiment with a cork of bottle but wide one, I put inside it a circular piece of iron,I put the the cork on a bowel of water, when the cork floats, I put a magnet under the cork , it attracts the iron so that the cork is at a steady position on water, when I rotated the bowel clockwise the cork started to spin counterclockwise but slowly, when I reversed the direction of rotation the cork spinned clockwise. Do those results match exactly with your original experiment? What was the corks rotation in relation to, the rotating pan or the room? If the cork stayed oriented to the room your hypothesis may be false. Do you think the magnetism could be applying any influence on the cork? Did you try it without the magnet? Try it as many different ways as you can, it will help you define your understanding of it. Edited May 25, 2014 by arc
yahya515 Posted May 27, 2014 Author Posted May 27, 2014 Do those results match exactly with your original experiment? No , the magnet and the piece of iron will never be parallel to each other perfectly, and the fluid itself cause resistance to spinning, to see that I took a bowel of water, the fluid was at rest, I rotate the bowel for seconds , when I stopped I put a floating object onto water, the object was rotating because the water was moving after I rotated the bowel , and that why such rotating did not appear clearly in the case of using a magnet, because the magnet will hamper motion , the magnet and the piece of iron will never be parallel to each other perfectly in order for the spinning of the object to appear clearly. What was the corks rotation in relation to, the rotating pan or the room? I tried it without a magnet, but the problem is I won't be able to rotate it faster, anyway, the cork was not pointing at a fixed point in room , the arrow was changing direction from South to east. when I reversed direction it was pointing South it changed to West. I think if you hang a mass with a string and rotate yourself, it is the same as you hang a mass with a string and you are at rest, because the earth rotates you around its axis, the difference is the speed and radius of rotation. that why any hanging object will possess a slow rotation.
John Cuthber Posted May 27, 2014 Posted May 27, 2014 I am still waiting for you to explain why you still believe in this idea after it has been shown to be wrong. Your idea predicts that the rotation of the earth should slow down and speed up regularly over the course of the year. But the measurements show that it doesn't. So why don't you accept that it is wrong? Also, you have not explained how the geostationary satellites work. Come to think of it, GPS wouldn't work properly either.
yahya515 Posted May 27, 2014 Author Posted May 27, 2014 I am still waiting for you to explain why you still believe in this idea after it has been shown to be wrong. Your idea predicts that the rotation of the earth should slow down and speed up regularly over the course of the year. But the measurements show that it doesn't. So why don't you accept that it is wrong? Also, you have not explained how the geostationary satellites work. Come to think of it, GPS wouldn't work properly either. the ratio ( v /r) is always constant, in order for the earth to mantain in an elliptical orbit , when it rotates around in the short radius it should slow down. so the angular velocity is the same.
John Cuthber Posted May 27, 2014 Posted May 27, 2014 "when it rotates around in the short radius it should slow down." But it does not slow down. So you are wrong.
swansont Posted May 27, 2014 Posted May 27, 2014 the ratio ( v /r) is always constant, in order for the earth to mantain in an elliptical orbit , when it rotates around in the short radius it should slow down. so the angular velocity is the same. Which violates conservation of angular momentum, which tells us that mvr stays the same. Another way of looking at it is Kepler's second law, that of sweeping out equal areas per unit time. A satellite speeds up as r decreases.
yahya515 Posted June 8, 2014 Author Posted June 8, 2014 My idea does not apply to rotation which involve centripetal force due to gravitation, there should be real contact to transform rotation, that interprets my experiments on earth and not universal systems, it is not the idea of changing the position and direction of motion which will cause another rotation, it is the idea of transforming rotation somehow.
swansont Posted June 8, 2014 Posted June 8, 2014 My idea does not apply to rotation which involve centripetal force due to gravitation, there should be real contact to transform rotation, that interprets my experiments on earth and not universal systems, it is not the idea of changing the position and direction of motion which will cause another rotation, it is the idea of transforming rotation somehow. You're talking about planets and orbits. What force is there other than gravitation?
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