Kirchhoff is for the birds...

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2024-05-19, 07:50:23
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Author Topic: Kirchhoff is for the birds... (Read 24005 times)

muDped	Re: Kirchhoff is for the birds... « Reply #25 on: 2019-06-23, 10:56:24 »
Group: Tinkerer Hero Member Posts: 3055	Quote from: TinMan As we have 2 lots of 15 turns,the voltages across each of those 15 turns will cancel each other out,and give us a value of 0v. Providing the two windings do in fact develop equal voltages. Was a measurement of those voltages taken at some point to assure complete cancellation? What other explanation could there possibly be? --------------------------- For there is nothing hidden that will not be disclosed, and nothing concealed that will not be known or brought out into the open.

TinMan	Re: Kirchhoff is for the birds... « Reply #26 on: 2019-06-23, 11:45:02 »
Group: Elite Experimentalist Hero Member Posts: 4649	Quote from: muDped on 2019-06-23, 10:56:24 Providing the two windings do in fact develop equal voltages. Was a measurement of those voltages taken at some point to assure complete cancellation? What other explanation could there possibly be? Yes the voltages have been measured,and there is a 4mVrms variation between the two. That is very close when the voltages measured are 1.32VRMS. But why would we expect any different,when both windings have the 1100 ohm series resistance,both windings have the same amount of turns ,using the same length of wire of the same size. So 1.326 minus 1.322 leaves us with 4mV. I think we can safely say there is more than a 4mV variation across the two LED/resistor combo's--don't you think ?,as the 10mm LEDs need 2.6 volts across them before they start to conduct. We can clearly see one pumping out the light,while the other is completely dead. Of course we can also place the scope across each LED to see what the voltage actually is. But the point here is that all the sumed voltages in the loop do not equal 0v,nor dose it come even close. ATM,we have around +2.71VRMS-somehow Brad --------------------------- Never let your schooling get in the way of your education.

poynt99	Re: Kirchhoff is for the birds... « Reply #27 on: 2019-06-23, 15:01:23 »
Group: Administrator Hero Member Posts: 3213 It's not as complicated as it may seem...	There is nothing wrong with the conclusion that KVL holds in Lewin's experiment. There is nothing wrong with the test methodology I used and put forward. The results clearly indicate that KVL holds. I have proven it on my bench. You are welcome to disagree, but I am not going down the rabbit hole being offered. Peace out. --------------------------- "Some scientists claim that hydrogen, because it is so plentiful, is the basic building block of the universe. I dispute that. I say there is more stupidity than hydrogen, and that is the basic building block of the universe." Frank Zappa

poynt99	Re: Kirchhoff is for the birds... « Reply #28 on: 2019-06-23, 20:23:57 »
Group: Administrator Hero Member Posts: 3213 It's not as complicated as it may seem...	Quote from: Matt Watts on 2014-03-18, 17:12:57 [youtube]http://www.youtube.com/watch?v=EwIk2gew-R8[/youtube] [youtube]http://www.youtube.com/watch?v=gJSEgANEkOo[/youtube] When dealing with B fields, your position of measurement matters. Just noticed, you guys are on top of this: http://www.overunityresearch.com/index.php?topic=739.0 Precisely. --------------------------- "Some scientists claim that hydrogen, because it is so plentiful, is the basic building block of the universe. I dispute that. I say there is more stupidity than hydrogen, and that is the basic building block of the universe." Frank Zappa

TinMan	Re: Kirchhoff is for the birds... « Reply #29 on: 2019-06-24, 00:23:36 »
Group: Elite Experimentalist Hero Member Posts: 4649	Quote from: poynt99 on 2019-06-23, 20:23:57 Precisely. Only with my setup,there are no B fields that can interact with any of the scope probes to cause measurement error. Brad --------------------------- Never let your schooling get in the way of your education.

poynt99	Re: Kirchhoff is for the birds... « Reply #30 on: 2019-06-24, 01:20:31 »
Group: Administrator Hero Member Posts: 3213 It's not as complicated as it may seem...	You should listen intently to ION, as he is 100% correct, and you are leading yourself astray once again. Here are some corrections for you to consider: a) In Lewin's original setup, and the one I tested, the E field is what is directly inducing the loop current, not the B field. b) In your toroid setup, the B field is what is inducing the loop current. c) When going around the loop to reconcile all the measured voltages, we ADD them, not subtract them as you did in your first video. In other words, the SUM of the series voltages in a loop is zero. The SUM of your two resistor measurements is 80.3mV. (see e) below) d) Proper measurement of the wire part of the loop is done around the outside of the toroid, and if you account for the polarity and voltage, you will find that when added to the other two resistor voltages, you will be left with something close to zero. e) Your "proper" measurement of the toroid section of the wire was about 81mV. The two resistor voltages summed is 73mV + 7.3mV = 80.3mV. Summed with the series-subtracting wire voltage leaves you with 0.7mV. KVL holds. --------------------------- "Some scientists claim that hydrogen, because it is so plentiful, is the basic building block of the universe. I dispute that. I say there is more stupidity than hydrogen, and that is the basic building block of the universe." Frank Zappa

TinMan	Re: Kirchhoff is for the birds... « Reply #31 on: 2019-06-24, 02:54:23 »
Group: Elite Experimentalist Hero Member Posts: 4649	Quote from: poynt99 on 2019-06-24, 01:20:31 You should listen intently to ION, as he is 100% correct, and you are leading yourself astray once again. Here are some corrections for you to consider: a) In Lewin's original setup, and the one I tested, the E field is what is directly inducing the loop current, not the B field. b) In your toroid setup, the B field is what is inducing the loop current. c) When going around the loop to reconcile all the measured voltages, we ADD them, not subtract them as you did in your first video. In other words, the SUM of the series voltages in a loop is zero. The SUM of your two resistor measurements is 80.3mV. (see e) below) d) Proper measurement of the wire part of the loop is done around the outside of the toroid, and if you account for the polarity and voltage, you will find that when added to the other two resistor voltages, you will be left with something close to zero. e) Your "proper" measurement of the toroid section of the wire was about 81mV. The two resistor voltages summed is 73mV + 7.3mV = 80.3mV. Summed with the series-subtracting wire voltage leaves you with 0.7mV. KVL holds. Im going to disagree with you Poynt,and i think you have it backwards. In Lewins setup,it is the B field cutting through the loop. In my setup,the B field is contained within the toroid. I have provided video's showing the loop shielded from any magnetic field by way of steel tubes placed through the center hole of the toroid,and the loop wire then threaded through that steel tube. The drawing i peovided clearly shows the electric field of a toroid,and also shows the B field is contained within the toroid core. Brad --------------------------- Never let your schooling get in the way of your education.

ion	Re: Kirchhoff is for the birds... « Reply #32 on: 2019-06-24, 03:16:24 »
Group: Elite Hero Member Posts: 3537 It's turtles all the way down	Brad Take a good look at the Loopy looped.jpg you have supplied. It is assumed there is a loop current of 1 ampere, OK we can agree on that. We can also agree that the loop current produces the designated voltages across the resistors per Ohms Law, even without measuring them. Now meditate on this: How does the 1 ampere come to exist in the loop and what is the actual voltage produced across the two wire segments? Hint: you show a "primary coil", now where is(are) the secondary coil(s)? Regards p.s. this is my last post for this evening, hitting the sack, maybe see you in the morning after a few cups of coffee.. ------------------------ Kirchhoff is for the birds... Loopy looped 1.JPG (29.76 kB, 523x559 - viewed 544 times.) --------------------------- "Secrecy, secret societies and secret groups have always been repugnant to a free and open society"......John F Kennedy

TinMan	Re: Kirchhoff is for the birds... « Reply #33 on: 2019-06-24, 05:29:34 »
Group: Elite Experimentalist Hero Member Posts: 4649	Quote from: ion on 2019-06-24, 03:16:24 Brad Take a good look at the Loopy looped.jpg you have supplied. It is assumed there is a loop current of 1 ampere, OK we can agree on that. We can also agree that the loop current produces the designated voltages across the resistors per Ohms Law, even without measuring them. Now meditate on this: How does the 1 ampere come to exist in the loop and what is the actual voltage produced across the two wire segments? Hint: you show a "primary coil", now where is(are) the secondary coil(s)? Regards p.s. this is my last post for this evening, hitting the sack, maybe see you in the morning after a few cups of coffee.. The 1 ampere is produce via the magnetic field cutting through the loop,which consists of A ,B, and the two resistors. As Lewin clearly states,the two connecting wires (A and B) are super conductive,and so with 1 ampere flowing through them,there will be 0 volts across them. As stated above,the secondary coil consist of A,B, and the two resistors. The 9 ohm resistor will have 9V across it,and the 1 ohm resistor will have 1V across it. So how dose this sum to 0 volts around the loop ?. If the measurement leads are on the same plane as the loop,they become the 3rd and 4th loop,and will develope there own voltage due to the magnetic field also cutting through those loops,which will give incorrect voltage values across the resistors. This is my very point when i say you cannot place the scope probe and ground around the toroid when trying to measure the voltage across the connecting wire that passes through the toroid,as you are doing the very same thing,and forming a second loop that the electric field is passing through. So in doing this,like the lewin test,you are reading an incorrect voltage across that small piece of wire. I know i am right on this,and have proven that. I also have other ways of showing the scope dose not read the correct voltage in doing it that way. All you are doing is forming a second loop,which is the short piece of wire through the toroid,and the scope it self. The voltage around lewins circuit dose not sum to 0,nor dose the voltage in any of my toroid circuits--ohms law clearly shows that. Kirchhoffs loop rule fails,but Faradays law holds,as dose ohms law. Brad --------------------------- Never let your schooling get in the way of your education.

ion	Re: Kirchhoff is for the birds... « Reply #34 on: 2019-06-24, 15:13:44 »
Group: Elite Hero Member Posts: 3537 It's turtles all the way down	author=TinMan link=topic=2369.msg75510#msg75510 date=1561350574] Quote The 1 ampere is produce via the magnetic field cutting through the loop,which consists of A ,B, and the two resistors. We agree on this Quote As Lewin clearly states,the two connecting wires (A and B) are super conductive,and so with 1 ampere flowing through them,there will be 0 volts across them. First assumption a fail, A and B are not superconductive, they are transformer secondaries and will have a voltage on them, they are active potential sources. Even if they were superconductive transformer secondaries they could still have voltage induced in them. Quote As stated above,the secondary coil consist of A,B, and the two resistors. Go back and meditate on what voltage you would actually expect the segments A and B to have developed in them.(Hint: not 0) Quote The 9 ohm resistor will have 9V across it,and the 1 ohm resistor will have 1V across it. So how dose this sum to 0 volts around the loop ?. Before you get to that question, you must answer how the resistors come to have a voltage impressed on them. When you identify the voltage sources that develop the current in the loop, it will be clear. Quote If the measurement leads are on the same plane as the loop,they become the 3rd and 4th loop,and will develope there own voltage due to the magnetic field also cutting through those loops,which will give incorrect voltage values across the resistors. Forget about measurement leads it is not important for this exercise as Ohms Law is all that is needed. Quote This is my very point when i say you cannot place the scope probe and ground around the toroid when trying to measure the voltage across the connecting wire that passes through the toroid,as you are doing the very same thing,and forming a second loop that the electric field is passing through. So in doing this,like the lewin test,you are reading an incorrect voltage across that small piece of wire. Then how do you normally measure the voltage on the secondary of a transformer. I have asked this before,but you did not reply? Quote I know i am right on this,and have proven that. Don't be so sure You have rigged the test to comply with the first erroneous premise of Lewin, that the segments are superconductive and will have zero volts on them. You actually made the correct measurement of 82mV but discarded this truthful measurement to comply with Lewin's error. Quote I also have other ways of showing the scope dose not read the correct voltage in doing it that way. All you are doing is forming a second loop,which is the short piece of wire through the toroid,and the scope it self. Forget all this and just demonstrate how you would normally read the secondary voltage of a toroidal transformer with a single turn secondary. Surely you don't thread the scope ground lead also through the toroid or all toroidal transformers would read zero volts using your method. Quote The voltage around Lewins circuit dose not sum to 0,nor dose the voltage in any of my toroid circuits--ohms law clearly shows that. Kirchhoffs loop rule fails,but Faradays law holds,as dose ohms law. Brad It does not sum to zero in Lewin's case because of Lewin's erroneous assumption. In following the erroneous assumption Kirchhoff fails. When you get rid of that assumption it works. Over and Out « Last Edit: 2019-06-24, 19:23:58 by ion » --------------------------- "Secrecy, secret societies and secret groups have always been repugnant to a free and open society"......John F Kennedy

F6FLT	Re: Kirchhoff is for the birds... « Reply #35 on: 2019-06-24, 17:34:18 »
Group: Experimentalist Hero Member Posts: 1987	Quote from: TinMan on 2019-06-24, 05:29:34 ... The 9 ohm resistor will have 9V across it,and the 1 ohm resistor will have 1V across it. So how dose this sum to 0 volts around the loop ?. ... A battery imposes a voltage, this potential difference generates the electric field, the electric field generates the force on the electrons and therefore the current. An induced voltage is the opposite, a force, contrary to what its unit suggest, the EMF. We have the force on the electrons first, so the current. Then, what the electrons encounter in their path, such as a resistance, will oppose the force and thus create potential differences along their path. If the circuit is open, the resistance is infinite, then a potential difference equal to the EMF is measured. When you have 10v between the two open terminals, you have also -10v along the conductor loop, not zero. The surprise of the measurements comes from there, it is the mistake to reason as if the EMF was the voltage of a battery. It's the force on the electrons and indirectly, a voltage. --------------------------- "Open your mind, but not like a trash bin"

TinMan	Re: Kirchhoff is for the birds... « Reply #36 on: 2019-06-25, 11:24:36 »
Group: Elite Experimentalist Hero Member Posts: 4649	author=ion link=topic=2369.msg75534#msg75534 date=1561385624] author=TinMan link=topic=2369.msg75510#msg75510 date=1561350574] Quote Go back and meditate on what voltage you would actually expect the segments A and B to have developed in them.(Hint: not 0) As there is 10 ohms of resistors in the loop,i would expect the voltage across A and B to be very low,as there resistance value would be very low. Quote Before you get to that question, you must answer how the resistors come to have a voltage impressed on them. Because they get a buildup of charge on one side,and a lesser amount on the other. Same as a water pipe that has water flowing through it,with a restrictor in the center of it. Quote When you identify the voltage sources that develop the current in the loop, it will be clear. It is the current in the loop that caused the voltage across the resistors and A and B. The voltage source is my SG. The electric field is what causes a current to flow in the loop. This flow of current in turn creates a magnetic field,as in all transformers. Quote Forget about measurement leads it is not important for this exercise as Ohms Law is all that is needed. Indeed. Quote Then how do you normally measure the voltage on the secondary of a transformer. I have asked this before,but you did not reply? Not by wrapping the scope leads around the transformer core to form another loop,where the leads are placed across only a small portion of the transformers turns. Quote You have rigged the test to comply with the first erroneous premise of Lewin, that the segments are superconductive and will have zero volts on them. You actually made the correct measurement of 82mV but discarded this truthful measurement to comply with Lewin's error. That 82mV shows exactly the voltage that would be had with a single loop. In order for that 82mV to be subtracted from the 82mV of the circuit,so as we end up with our 0 volts,it would have to be of the opposite polarity to that of the single loop,so as when added to the sum of the two resistor's,it will be close to 0,but it is of the same polarity,not opposite.. On that note,with the scope probe through the toroid,and clipped to the ground lead of the probe,we get 82mV . Now,what is the scope measuring if it is not measuring it's own circuit voltage due to the now newly formed looped circuit--which is the scope and leads them self. Quote Poynt: d) Proper measurement of the wire part of the loop is done around the outside of the toroid, and if you account for the polarity and voltage, you will find that when added to the other two resistor voltages, you will be left with something close to zero. So this means that the polarity should be opposite to that of the loop. When the resistor voltages are in the + side of the wave,then the probe looped around the toroid should be in the - side of the wave,so as when added they sum to 0. Now,using the differential measurement method,where the ground leads of the scope are floating,i can accurately measure the voltage across all points of the loop using two channels of the scope. The voltage measured across A and B are 2mV and 3mV Across the two resistors,we have for the 1k 78mV,and for the 100R 7.8mV So i ask again,how dose that all add to 0 volts around the loop?. Quote Forget all this and just demonstrate how you would normally read the secondary voltage of a toroidal transformer with a single turn secondary. Surely you don't thread the scope ground lead also through the toroid or all toroidal transformers would read zero volts using your method. Is the secondary looped on it self as the one we are testing,or is it open ? I answered this question above. Quote It does not sum to zero in Lewin's case because of Lewin's erroneous assumption. In following the erroneous assumption Kirchhoff fails. When you get rid of that assumption it works. Forget Lewin for a moment,and let's look at my circuit. Below is a diagram. Please fill in the voltages for all test points,so as i can see how you get them to all sum to 0. Thanks Brad --------------------------- Never let your schooling get in the way of your education.

ion	Re: Kirchhoff is for the birds... « Reply #37 on: 2019-06-25, 16:28:23 »
Group: Elite Hero Member Posts: 3537 It's turtles all the way down	Here is the proper solution to the Loop loop circuit and the questions I posed in reply #32 and 34. Note that the segments A and B are transformer secondaries and will have induced in them the EMF which creates the loop current. They do not have zero volts, rather they have the missing EMF's that solve KVL=0 around the loop. Whoever came up with the idea that a superconducting secondary of a transformer must have zero volts is completely wrong and does not understand induction. If it was Lewin, then too bad for him. Does not matter how low the resistance of a transformer secondary is, it can still have a large voltage induced into it and EMF appears. For a simple understanding just consider it to be charge separation within the low resistance conductor. Note that for this case we assume the resistors to be to be very thin disc type so we do not have to consider the small amount of induction directly into the resistors. (lumped element mode). If we don't do this then we would have to apportion lengths of conductors into the solution, which could get messy but still yields KVL=0. You might also consider this video by Mehdi: https://www.youtube.com/watch?v=Q9LuVBfwvzA ------------------------ Kirchhoff is for the birds... Loopy Loop corrected.png (33.16 kB, 473x469 - viewed 437 times.) Kirchhoff is for the birds... Solution.png (6.13 kB, 511x373 - viewed 422 times.) « Last Edit: 2019-06-25, 16:53:44 by ion » --------------------------- "Secrecy, secret societies and secret groups have always been repugnant to a free and open society"......John F Kennedy

poynt99	Re: Kirchhoff is for the birds... « Reply #38 on: 2019-06-25, 17:35:30 »
Group: Administrator Hero Member Posts: 3213 It's not as complicated as it may seem...	Excellent, and of course 100% correct ION! --------------------------- "Some scientists claim that hydrogen, because it is so plentiful, is the basic building block of the universe. I dispute that. I say there is more stupidity than hydrogen, and that is the basic building block of the universe." Frank Zappa

TinMan	Re: Kirchhoff is for the birds... « Reply #39 on: 2019-06-26, 00:31:50 »
Group: Elite Experimentalist Hero Member Posts: 4649	Quote from: ion on 2019-06-25, 16:28:23 Here is the proper solution to the Loop loop circuit and the questions I posed in reply #32 and 34. Note that the segments A and B are transformer secondaries and will have induced in them the EMF which creates the loop current. They do not have zero volts, rather they have the missing EMF's that solve KVL=0 around the loop. Whoever came up with the idea that a superconducting secondary of a transformer must have zero volts is completely wrong and does not understand induction. If it was Lewin, then too bad for him. Does not matter how low the resistance of a transformer secondary is, it can still have a large voltage induced into it and EMF appears. For a simple understanding just consider it to be charge separation within the low resistance conductor. Note that for this case we assume the resistors to be to be very thin disc type so we do not have to consider the small amount of induction directly into the resistors. (lumped element mode). If we don't do this then we would have to apportion lengths of conductors into the solution, which could get messy but still yields KVL=0. You might also consider this video by Mehdi: https://www.youtube.com/watch?v=Q9LuVBfwvzA Ion I knew the A and B measurement you would write in before i even posted the question. I assumed you would make the loop voltages sum to 0. On paper it may look good,but it is an incorrect assumption. There is no 5v across A and B,nor dose there have to be in reality. Brad --------------------------- Never let your schooling get in the way of your education.

Magluvin	Re: Kirchhoff is for the birds... « Reply #40 on: 2019-06-26, 01:24:31 »
Group: Mad Scientist Hero Member Posts: 546	Quote from: ion on 2019-06-25, 16:28:23 Here is the proper solution to the Loop loop circuit and the questions I posed in reply #32 and 34. Note that the segments A and B are transformer secondaries and will have induced in them the EMF which creates the loop current. They do not have zero volts, rather they have the missing EMF's that solve KVL=0 around the loop. Whoever came up with the idea that a superconducting secondary of a transformer must have zero volts is completely wrong and does not understand induction. If it was Lewin, then too bad for him. Does not matter how low the resistance of a transformer secondary is, it can still have a large voltage induced into it and EMF appears. For a simple understanding just consider it to be charge separation within the low resistance conductor. Note that for this case we assume the resistors to be to be very thin disc type so we do not have to consider the small amount of induction directly into the resistors. (lumped element mode). If we don't do this then we would have to apportion lengths of conductors into the solution, which could get messy but still yields KVL=0. You might also consider this video by Mehdi: https://www.youtube.com/watch?v=Q9LuVBfwvzA I agree also. I wrote this in the other thread but then this thread popped up.... "If the wires between the resistors are the 'source' to the circuit by being induced by flux from the driver coil, then there will also be a voltage measured across each wire due to the pressures of charge induced in the wires met with the impedance of the resistors, whether the conductors are normal or superconducting. A shift of electrons from one end of the wire to the other, between the resistors, will show voltage across that wire. Just because the wires are a current source, does not mean that they cannot have voltage read across them when in the circuit. And, if it measures 0v between the center of the length of one wire to the center of the length of the other wire, then we have another thing going on in the wires, if the resistors have different voltages at that point in time. One half length of the wire should have more voltage across it than the other, in order for there to be 0v measured between the 2 centers of the wires. With the smaller value resistor, the 2 halves of the induced wires connected to it will have higher voltage values than the 2 halves connected to the higher value resistor, all in order to measure 0v any where around the circuit as per Kirchhoff's experiment." Its prob not all correct, but close. Mags

TinMan	Re: Kirchhoff is for the birds... « Reply #41 on: 2019-06-26, 04:40:36 »
Group: Elite Experimentalist Hero Member Posts: 4649	Quote from: poynt99 on 2019-06-25, 17:35:30 Excellent, and of course 100% correct ION! In the case of my setup,unfortunately not. Brad --------------------------- Never let your schooling get in the way of your education.

TinMan	Re: Kirchhoff is for the birds... « Reply #42 on: 2019-06-26, 12:31:10 »
Group: Elite Experimentalist Hero Member Posts: 4649	Here are the actual voltages across my circuit. Area's A,B and C where measured via normal scope probing,as area D traverses the toroid center. Confirmation-- Area's A,B,C and D where measured using the differential probing method. Each method agree's with the other. Brad ------------------------ Kirchhoff is for the birds... Loopy looped actual voltages.JPG (12.46 kB, 488x318 - viewed 353 times.) --------------------------- Never let your schooling get in the way of your education.

ion	Re: Kirchhoff is for the birds... « Reply #43 on: 2019-06-26, 15:00:57 »
Group: Elite Hero Member Posts: 3537 It's turtles all the way down	Quote from: TinMan on 2019-06-26, 12:31:10 Here are the actual voltages across my circuit. Area's A,B and C where measured via normal scope probing,as area D traverses the toroid center. Confirmation-- Area's A,B,C and D where measured using the differential probing method. Each method agree's with the other. Brad Brad, now you are mixing apples and oranges. You are now stating that you are using a toroid induction which does not agree with a solenoid induction as shown in your present drawing (circle in the center of drawing). The voltages I referred to in the corrected drawing were for solenoid induction per Lewin. Naturally the induction distribution will be different for the toroid method vs. solenoid method. Provide a picture of your actual test setup and actual probing points as the latest drawing is different than reality. --------------------------- "Secrecy, secret societies and secret groups have always been repugnant to a free and open society"......John F Kennedy

TinMan	Re: Kirchhoff is for the birds... « Reply #44 on: 2019-06-26, 23:32:28 »
Group: Elite Experimentalist Hero Member Posts: 4649	Quote from: ion on 2019-06-26, 15:00:57 Brad, now you are mixing apples and oranges. You are now stating that you are using a toroid induction which does not agree with a solenoid induction as shown in your present drawing (circle in the center of drawing). The voltages I referred to in the corrected drawing were for solenoid induction per Lewin. Naturally the induction distribution will be different for the toroid method vs. solenoid method. Provide a picture of your actual test setup and actual probing points as the latest drawing is different than reality. Yes Sorry about the drawing. Forgot to change it. I will change it tonight after the work day is done. But for now,just remove the solenoid,and place the toroid around link D. You now have my circuit and voltage values for each part of the circuit. Whether by solenoid of toroid,both induce current flow through the secondary loop. Brad --------------------------- Never let your schooling get in the way of your education.

poynt99	Re: Kirchhoff is for the birds... « Reply #45 on: 2019-06-27, 03:09:49 »
Group: Administrator Hero Member Posts: 3213 It's not as complicated as it may seem...	Why is it thought that it is necessary to thread the meter leads through the centre of the toroid in order to avoid influence from the fields and to get an accurate reading? After some reflection on the toroid configuration, I am in agreement that the E field is the action mechanism on the wire loop. However, in the solenoid configuration (the original one), again it is the E field that acts upon the loop. With the toroid configuration, and with the E fields in mind, spanning the toroid from the outside avoids influence on the measurement leads. Threading the lead through the toroid is actually what does influence the measurement. Why? A second loop is formed by the leads and part of the loop, and since the E field is now acting simultaneously on both halves of this second loop, of course the result is that 0V is induced in the loop, and 0V will be measured. Imagine taking your loop with the resistors (no voltmeter leads) and elongating it so it could be threaded through the centre of the toroid. Do you think any emf will be induced in the loop? I hope not. Well, same scenario occurs with the measurement leads when they are thread through; you are nulling out the measurement by feeding both "sides" of the loop into the toroid. Measuring across (not through) the toroid is the correct form to avoid influence from the fields. --------------------------- "Some scientists claim that hydrogen, because it is so plentiful, is the basic building block of the universe. I dispute that. I say there is more stupidity than hydrogen, and that is the basic building block of the universe." Frank Zappa

TinMan	Re: Kirchhoff is for the birds... « Reply #46 on: 2019-06-27, 03:32:08 »
Group: Elite Experimentalist Hero Member Posts: 4649	Quote from: poynt99 on 2019-06-27, 03:09:49 Why is it thought that it is necessary to thread the meter leads through the centre of the toroid in order to avoid influence from the fields and to get an accurate reading? After some reflection on the toroid configuration, I am in agreement that the E field is the action mechanism on the wire loop. However, in the solenoid configuration (the original one), again it is the E field that acts upon the loop. With the toroid configuration, and with the E fields in mind, spanning the toroid from the outside avoids influence on the measurement leads. Threading the lead through the toroid is actually what does influence the measurement. Why? A second loop is formed by the leads and part of the loop, and since the E field is now acting simultaneously on both halves of this second loop, of course the result is that 0V is induced in the loop, and 0V will be measured. Imagine taking your loop with the resistors (no voltmeter leads) and elongating it so it could be threaded through the centre of the toroid. Do you think any emf will be induced in the loop? I hope not. Well, same scenario occurs with the measurement leads when they are thread through; you are nulling out the measurement by feeding both "sides" of the loop into the toroid. Measuring across (not through) the toroid is the correct form to avoid influence from the fields. I am glad you agree that it is the E field that is the source of induction in the secondary loop. Thats one issue sorted. Now,the measured voltages around the loop. I maintain that trying to measure link D by having the scope probes around the toroid is wrong. Doing that you are not measuring the voltage across link D,you are measuring the voltage of a complete new loop around the toroid,and this second loops voltage is governed by the load placed on the toroid by the first loop,and where that second loops voltage will be the same as the first loops voltage. Using the differential method,we can obtain accurate voltages around the loop. These voltages conform to the voltages read using normal scope probing. At no point do the sum of the voltages sum to 0,and that is a verifiable fact. I do not understand as to why you think this is impossible,as this can be achieved in many ways,like a looped water circuit and pumps,where the pressures around the loop do not sum to 0. Brad --------------------------- Never let your schooling get in the way of your education.

poynt99	Re: Kirchhoff is for the birds... « Reply #47 on: 2019-06-27, 04:24:44 »
Group: Administrator Hero Member Posts: 3213 It's not as complicated as it may seem...	There is no field interaction when the voltmeter or scope leads are outside the toroid. When inside the toroid, there is. Surely you see that? When you are doing the differential measurement, do you also somehow put one scope probe through the toroid? --------------------------- "Some scientists claim that hydrogen, because it is so plentiful, is the basic building block of the universe. I dispute that. I say there is more stupidity than hydrogen, and that is the basic building block of the universe." Frank Zappa

TinMan	Re: Kirchhoff is for the birds... « Reply #48 on: 2019-06-27, 05:50:42 »
Group: Elite Experimentalist Hero Member Posts: 4649	Quote from: poynt99 on 2019-06-27, 04:24:44 There is no field interaction when the voltmeter or scope leads are outside the toroid. When inside the toroid, there is. Surely you see that? When you are doing the differential measurement, do you also somehow put one scope probe through the toroid? Yes,putting the scope ground through the toroid is incorrect,as is having it around the toroid. And no,neither of the scope probes are !somehow! through the toroid,as both ground leads are floating. The fact that both links have very nearly the same voltage when using the differential probing method,and there resistance value is almost exact to one another,and the fact that the current flowing through the loop is the same at any two points,is proof that the correct voltage is being displayed via the differential method across the bottom link that passes through the toroid. No matter how you try,the summed voltages around the loop will never sum to 0. Im sure you have a small toroid inductor and a couple of resistors lying around Poynt. The circuit takes only a couple of minutes to set up. If not,then i will take the time tonight and shoot a video of my test methods for you to see--which i will do regardless. At this point,i would be interested in seeing what a sim says. Is it possible to set the sim up to induce a current through the loop via a toroid as in my setup ?. Brad --------------------------- Never let your schooling get in the way of your education.

TinMan	Re: Kirchhoff is for the birds... « Reply #49 on: 2019-06-27, 13:42:16 »
Group: Elite Experimentalist Hero Member Posts: 4649	Quote from: poynt99 on 2019-06-24, 01:20:31 You should listen intently to ION, as he is 100% correct, and you are leading yourself astray once again. Here are some corrections for you to consider: a) In Lewin's original setup, and the one I tested, the E field is what is directly inducing the loop current, not the B field. b) In your toroid setup, the B field is what is inducing the loop current. c) When going around the loop to reconcile all the measured voltages, we ADD them, not subtract them as you did in your first video. In other words, the SUM of the series voltages in a loop is zero. The SUM of your two resistor measurements is 80.3mV. (see e) below) d) Proper measurement of the wire part of the loop is done around the outside of the toroid, and if you account for the polarity and voltage, you will find that when added to the other two resistor voltages, you will be left with something close to zero. e) Your "proper" measurement of the toroid section of the wire was about 81mV. The two resistor voltages summed is 73mV + 7.3mV = 80.3mV. Summed with the series-subtracting wire voltage leaves you with 0.7mV. KVL holds. Poynt I need to address these issue's with you,as i think you really need to take another look at this. So far,here are some of the events that have taken place in this thread. In reply 28,you highlighted a quote from Matt-Watts -->When dealing with B fields, your position of measurement matters. To which you replied-->Precisely. Then in reply 30 you state-- a) In Lewin's original setup, and the one I tested, the E field is what is directly inducing the loop current, not the B field. It is my belief that both the E and B field played a part in the Lewin circuit,and i will get to that later,after i have assembled Lewins original test setup along side mine. In post 11 i state-->the secondary loop is induced by the electric field,and not the magnetic field. In post 30 you also state this-- b) In your toroid setup, the B field is what is inducing the loop current. In post 31 i state--Im going to disagree with you Poynt,and i think you have it backwards. In Lewins setup,it is the B field cutting through the loop. In my setup,the B field is contained within the toroid. Then in reply 45 you state-After some reflection on the toroid configuration, I am in agreement that the E field is the action mechanism on the wire loop. However, in the solenoid configuration (the original one), again it is the E field that acts upon the loop. I am happy that you agree with me about it being the E field that is inducing the current in my loop,as that means all my hard work and time in gaining an understanding into all forms of induction, by way of being self taught and my time spent on the bench,and my own thought's is paying off. Now,while i wish to remain focused mainly on my toroid setup,i would like to reflect a little on Lewins original setup. You state it is the E field inducing the single loop,but you also seem to agree with Matt as well when he says-- When dealing with B fields, your position of measurement matters Now,the way i see it(these are my thought's),the E field is inducing the current through the secondary loop of Lewins setup,and the B field is inducing the voltage in the loops of the measuring equipment leads. I confirmed this on my bench-->the E field will not induce a current in the secondary loop when that secondary loop is not around the circumference of the primary coil. If the secondary loop is sitting beside the primary,and not wrapped around the primary coil,no current will be induced via the E field. Now,this is not the case with the B field,where the secondary loop will be induced if that secondary loop is sitting beside the primary coil,and not wrapped around it. In saying all that,here is the problem i see in the testing of Lewin's circuit. The secondary loop is induced by the E field(as you state),but the measuring equipment leads were induced by the B field !apparently!,in accordance with your reply to Matts comment regarding the B field-->When dealing with B fields, your position of measurement matters,to which you reply !Precisely! Now the biggest problem here is the phase relationship between the induced voltage of the secondary loop by the E field,and the induced voltage of the measurement equipment leads by the B field. These two induced voltages should have been 90* out of phase,but in your tests,they were all in phase How do we know this? Well if it is the E field inducing the EMF in the secondary,then the primary and secondary voltage phase relationship should be in phase. If it is the B field inducing the EMF in the secondary,then voltage phase relationship between the primary and secondary should be 90,as the magnetic field in the primary is a result of current flow,and we know the current lags the voltage by 90 in an inductor. So i have to wonder,which voltage the measurement equipment was actually measuring?. Was it the voltage across the resistors in the secondary loop induced by the E field,or the induced voltage in the third loop formed by the measurement equipments lead's which was induced by the B field?. And what is the outcome of mixing two different circuits,where 1 has an in phase relationship with the primary inductor's voltage,and the other has a 90* phase relationship with the primary inductor's voltage. If i am wrong about all this,could you please explain as to why you agree with Matts comment about the B field,but state it is the E field that is inducing the EMF in Lewin's experiment ?. Thanks Brad --------------------------- Never let your schooling get in the way of your education.

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