But as the spaceship moves it interacts with the outside. This means that exterior forces are acting on the spaceship so it is no longer a closed system.
I do not need to go into detail to explain the error of your arguments regarding conservation laws and newtonians will be pleased that this thought experiment includes third law as well.
Quote from: chazemz on 09/11/2017 05:31 pmBut as the spaceship moves it interacts with the outside. This means that exterior forces are acting on the spaceship so it is no longer a closed system.So you actually aren't talking about a closed system at all, you are talking about an open system. To describe anything about this system's behavior, you need to define exactly what it is interacting with outside, and what these forces are.Quote from: chazemz on 09/11/2017 05:31 pmI do not need to go into detail to explain the error of your arguments regarding conservation laws and newtonians will be pleased that this thought experiment includes third law as well.Error of what arguments? The only thing I stated is the simple fact that batteries don't store momentum. And yes, you have to respond to arguments if you want to have a conversation.
If you want to go further, take the spaceship into a region of nothing and then fire the cannon. With nothing to interact with, it will remain a closed system. So theoretically speaking you can move a closed system and conserve momentum.
I was not referring to you in the arguments.
Mmmmm, I agree, but is momentum stored energy?
Momentum and energy are not the same thing. Mmmmm, I agree, but is momentum stored energy?
If a spaceship was to be fitted with a device that could move the spaceship from within and the spaceship was to move within the confines of the known universe, as soon as the spaceship begins to move it can no longer be classed as a closed system.
The battery could be described as a rocket engine in that it converts stored chemical energy into kinetic energy.
Quote from: chazemz on 09/12/2017 12:50 pmIf a spaceship was to be fitted with a device that could move the spaceship from within and the spaceship was to move within the confines of the known universe, as soon as the spaceship begins to move it can no longer be classed as a closed system.Not true, the spacecraft moving does not make it an open system. You had correctly mentioned previously that external forces are involved in making it an open system. You have not described any forces though. We are talking about a spacecraft in deep space. There are no forces defined on it, so it is a closed system, unless you describe external forces acting on it.Quote from: chazemz on 09/12/2017 12:50 pmThe battery could be described as a rocket engine in that it converts stored chemical energy into kinetic energy.Momentum conservation says that this doesn't make sense. You can't just convert chemical energy to kinetic energy, you have to balance conservation of momentum by expelling some sort of exhaust.
The rocket engine does it by combustion, the battery would do it by using the flow of electrical energy/power..So Watts = joules = newtons.
You transfer energy from the battery onto the body of the spaceship. In low earth orbit it would then change to an open system.
It would be easier if we could define when a “closed system” is a “closed system” which is what I have tried to do in the earlier posts. If we place a charged battery into the spaceship and close all the hatches, have we got a” closed system”? So another little thought experiment! We take the cannon outside the spaceship and leave a hatch open. We fire the cannon so the cannon ball flies through the hatch and then close the hatch. What have we got?. Technically it is a “closed system” since the cannon ball has not interacted with the spaceship. But we have an “open system” in waiting since we can tell the future and know what is going to happen. And as soon as we define the system as “closed” does the cannon ball become part of the system so cannot be referred to as “exterior”
With reference to the exhaust, I need to know how you define “conserve”Would it not be better to use the term energy/momentum are always “accounted for”?
*snip*With reference to the exhaust, I need to know how you define “conserve”Would it not be better to use the term energy/momentum are always “accounted for”?
You simply have to define what your system is. If you are going to leave the hatch open and let the cannon ball fly out you can either include the cannon ball in the system or not.The cannon ball flies INTO the spaceship, then the hatch is closed.Is it then classed as a "closed system".If it is a "closed system" what will happen to conserve momentum in the system.
I would like to ask some questions. I am in a spacecraft (I have grip on the floor) and at one end a spring is attached to the wall. I hold the spring and begin to walk backwards, extending the spring. 1) What will happen to the spacecraft as I walk backwards? 2) What will happen to the spacecraft when I let go of the spring? 3) What will happen to the spacecraft when the spring has returned to its original state?
Quote from: chazemz on 09/16/2017 11:11 amI would like to ask some questions. I am in a spacecraft (I have grip on the floor) and at one end a spring is attached to the wall. I hold the spring and begin to walk backwards, extending the spring. 1) What will happen to the spacecraft as I walk backwards? 2) What will happen to the spacecraft when I let go of the spring? 3) What will happen to the spacecraft when the spring has returned to its original state?Honestly I think it would be more helpful for you to try to work out the answer yourself, keeping in mind that the combined center of mass of the spaceship and all objects inside it will not move. In this case that refers to the hull, you, and the spring. Drawing a diagram may help with this.Note that to simplify things in mass-spring systems, physicists often assume that a spring has no mass, which is fine when masses attached to either end of the spring have significantly more mass than the spring. Since you are letting go of one end of the spring, there is no mass attached to that end, so you can't consider the spring massless if you want to see the dynamics of the spring retracting.
Quote from: chazemz on 09/11/2017 06:56 pmMomentum and energy are not the same thing. Mmmmm, I agree, but is momentum stored energy?No. Momentum and kinetic energy are not the same thing either. They are related, but not at all the same. Kinetic energy is 1/2 the product of the mass times velocity squared. Ek = 1/2 mv^2Momentum is mass times velocity. p = mvTwo objects with the same kinetic energy only have the same momentum if they also have the same mass.
With reference to the EM drive thread there appears to be a lot of “violates this conservation law” and “violates that conservation law” when I am of the opinion that what you are in fact doing is preserving third law. Commenting earlier on conservation of energy/momentum I put forward a simple experiment asking what would happen with a five ball newton's cradle if you raised two balls and let them go so they collided with the remaining three balls. We were in agreement that two balls must come out the other side since if one ball came out at twice the velocity momentum would be conserved but not kinetic energy I then asked if nature treats momentum and energy as the same and when nature conserves “it accounts for”.So on this point I would like to ask a question: if we have a spaceship that has a surrounding skin that you are calling “the boundary”and I fit solar panels to the outside ( we are assuming that we have a device inside the spaceship that transfers energy/ momentum to the spaceship from the solar panels), if the energy/momentum in equals the energy/momentum stored plus losses, since the energy/momentum comes from outside the boundary am I to assume that all is well?For the Newtonians among you we are not looking at third law in this instance, just conservation of energy/momentum.
I am on your wavelength here (no pun intended), although there is a school of thought that says a photon has momentum but no mass?
When I let go of the magnets one magnet will accelerate and the other magnet will decelerate.
If I turn so that I am facing the direction of travel and repeat the experiment, what will now happen when I release the magnets?
What about energy conservation?
Quote from: chazemz on 09/26/2017 06:56 pmWhat about energy conservation?Do you have a specific question about it? The last scenario you described simply involves conversion of potential energy to kinetic energy.
Quote from: meberbs on 09/26/2017 07:35 pmQuote from: chazemz on 09/26/2017 06:56 pmWhat about energy conservation?Do you have a specific question about it? The last scenario you described simply involves conversion of potential energy to kinetic energy.Well there are numerous questions that can be asked but we will start with a specific one. When I let go of the magnets they will, as you have stated, accelerate towards one another. Using inverse cube we know that the rate of acceleration will rise dramatically as the distance between them decreases. So where are the magnets getting their energy/momentum from?
The last scenario you described simply involves conversion of potential energy to kinetic energy.
You are evading the question. The magnets will accelerate at ninety degrees to the direction of travel. As they accelerate, since they have mass, their momentum and kinetic energy will increase. Where is this energy coming from?
Quote from: chazemz on 09/27/2017 04:19 pmYou are evading the question. The magnets will accelerate at ninety degrees to the direction of travel. As they accelerate, since they have mass, their momentum and kinetic energy will increase. Where is this energy coming from?You had to do "work" to bring the two magnets together. That stores potential energy. When you release them, that energy that YOU put in is released as they separate and converted into their motion.
Quote from: chazemz on 09/27/2017 04:19 pmYou are evading the question. The magnets will accelerate at ninety degrees to the direction of travel. As they accelerate, since they have mass, their momentum and kinetic energy will increase. Where is this energy coming from?I didn't avoid anything. I already answered this exact question twice.For the third time: Potential energy.https://en.wikipedia.org/wiki/Potential_energyAnd to be technical (which you should be when talking about physics) It is only their kinetic energy that increases. Total energy includes the potential energy, and therefore stays constant. And again, total momentum does not change.
I am really pleased that you have introduced potential energy, we will discuss this at a later date.So to be technical, both of you are saying that after the two magnets have joined, the velocity of the two magnets is the same as when they were released?
No, that was not my next question. I am however getting excited here. What you are saying is that the magnets can travel the extra distance without the need for any extra energy. Just to be cautious would this not contravene conservation of energy?
I feel we have covered enough ground to attempt a little game of chess with nature.
There was an objection raised that the device was using the initial counter rotation to enable the end result
Quote from: chazemz on 10/12/2017 04:44 pmI feel we have covered enough ground to attempt a little game of chess with nature.This is a terrible analogy. Nature is not the opponent in a game, if anything it is the rules of the game.Quote from: chazemz on 10/12/2017 04:44 pmThere was an objection raised that the device was using the initial counter rotation to enable the end resultYou apparently did not understand a thing that was said to you. The objection is that anyone who can do force balances (or torque balances in this case) would see that the angular momentum gained by the device at the end of the video was transferred to the device from the Earth through the string.You also only talked about conservation of energy in this post. Energy that allows the device to acquire kinetic energy clearly comes from the power supplied to the motor. The issue you are not recognizing is the completely separate question of momentum conservation (specifically angular momentum).The rest of your description fall back to your previous issues with communication, where you refer to adding a counter rotating device without explaining what part of the device it is attached to and whether it is counter rotating relative to the body (wooden part) or the arms.
Can you have kinetic energy without momentum?
angular momentum gained by the device at the end of the video was transferred to the device from the Earth through the stringHow?
Quote from: chazemz on 10/12/2017 06:54 pmangular momentum gained by the device at the end of the video was transferred to the device from the Earth through the stringHow?The string applies a torque. This was explained to you repeatedly in the other thread. You can easily see the torque by taking your device (while it is off), and rotating it 180 degrees. You will see the string then cause it to rotate back to the rest position (and then oscillate back and forth until dissipative forces such as air resistance bring it to rest).
Quote from: meberbs on 10/12/2017 07:04 pmQuote from: chazemz on 10/12/2017 06:54 pmangular momentum gained by the device at the end of the video was transferred to the device from the Earth through the stringHow?The string applies a torque. This was explained to you repeatedly in the other thread. You can easily see the torque by taking your device (while it is off), and rotating it 180 degrees. You will see the string then cause it to rotate back to the rest position (and then oscillate back and forth until dissipative forces such as air resistance bring it to rest).And I repeatedly told you that the string is not wound when the power is switched off. So the string applies no torque to the device at that moment.
Quote from: chazemz on 10/12/2017 07:25 pmQuote from: meberbs on 10/12/2017 07:04 pmQuote from: chazemz on 10/12/2017 06:54 pmangular momentum gained by the device at the end of the video was transferred to the device from the Earth through the stringHow?The string applies a torque. This was explained to you repeatedly in the other thread. You can easily see the torque by taking your device (while it is off), and rotating it 180 degrees. You will see the string then cause it to rotate back to the rest position (and then oscillate back and forth until dissipative forces such as air resistance bring it to rest).And I repeatedly told you that the string is not wound when the power is switched off. So the string applies no torque to the device at that moment.And you have been repeatedly told the state of the string when the device is turned off is irrelevant. While the device is on, the string applies torques. The net result of all of these torques while the device is on is the angular momentum the device has at the moment that you turn it off.
Quote from: meberbs on 10/12/2017 07:58 pmAnd you have been repeatedly told the state of the string when the device is turned off is irrelevant. While the device is on, the string applies torques. The net result of all of these torques while the device is on is the angular momentum the device has at the moment that you turn it off.The state of the string when the device is switched off is everything. It is the only thing that can apply an exterior force(torque) to the device at that moment. Since the string applies zero torque at that time, it has no influence on the observed result.
And you have been repeatedly told the state of the string when the device is turned off is irrelevant. While the device is on, the string applies torques. The net result of all of these torques while the device is on is the angular momentum the device has at the moment that you turn it off.
Quote from: chazemz on 10/13/2017 02:56 pmQuote from: meberbs on 10/12/2017 07:58 pmAnd you have been repeatedly told the state of the string when the device is turned off is irrelevant. While the device is on, the string applies torques. The net result of all of these torques while the device is on is the angular momentum the device has at the moment that you turn it off.The state of the string when the device is switched off is everything. It is the only thing that can apply an exterior force(torque) to the device at that moment. Since the string applies zero torque at that time, it has no influence on the observed result.Which words in my previous post did you not understand? Your response sounds like you did not read anything other than the first sentence of my post, because you did not address the simple fact that the string had already transferred angular momentum to the device. You can clearly see in the video that the device has angular momentum just before you turn it off. Therefore, it doesn't need any more torques applied to it for it to continue to spin.
The acceleration of the rotor arms has nothing to do with the string.
Since there is no counter rotation of the body when the rotor arms accelerate just before switch off,
being wrong is good, it means I am learning. We could go round and round (no pun intended) with the string so I am going to move on with my next post.
Going back to the thought experiment with the magnets. When I am facing the direction of travel and let go of the magnets, as the magnets accelerate towards each other, does their mass increase?
I fix myself to the spacecraft and fix one of the magnets to myself and pull the other magnet away from the one that is attached to me. I know that the magnets attract with equal magnitude and opposite in direction so the spacecraft will not move
There are some points to think about. With regard to two magnets attracting each other, could anyone advise me on a situation I am thinking about. I am in a small spacecraft that is positioned 50 meters from a space station that I need to get to. I have no engines and it would appear that my situation is hopeless. I do have a basic understanding of classical physics. On board I have two magnets so I hatch a cunning plan. I fix myself to the spacecraft and fix one of the magnets to myself and pull the other magnet away from the one that is attached to me. I know that the magnets attract with equal magnitude and opposite in direction so the spacecraft will not move (see bootstrapping) when I do this. However when I let the magnet go I can now use this attraction to help me. As the free magnet accelerates towards me, due to third law, I and so the spacecraft will move towards the free magnet, reducing the distance between me and the space station by a tiny amount. If I repeat this process many times I am able to reach my destination with no exhaust. So using classical physics it is easy to achieve what some people believe to be impossible?
The magnets apply equal and opposite forces when they are pulled apart, it is called statics. When I am holding the magnet it is part of my system. When I let it go.It is external to me. You are expending energy to produce baby steps of motion, think of the cannon. The space craft will move and eventually reach the space station.
Quote from: chazemz on 10/15/2017 11:21 amGoing back to the thought experiment with the magnets. When I am facing the direction of travel and let go of the magnets, as the magnets accelerate towards each other, does their mass increase?No.You are only converting potential energy into kinetic energy. Thus the energy of the entire system has not changed and so mass has not changed from a relativistic point of view. Which direction you are facing is irrelevant.If you were to let the magnets collide thus converting the kinetic energy into thermal energy and then let that thermal energy radiate away then the mass of the system would decrease. If you were then to pull the magnets apart thus adding potential energy to the system then their mass would increase.
Quote from: chazemz on 10/16/2017 07:14 pmThe magnets apply equal and opposite forces when they are pulled apart, it is called statics. When I am holding the magnet it is part of my system. When I let it go.It is external to me. You are expending energy to produce baby steps of motion, think of the cannon. The space craft will move and eventually reach the space station.Every force has an equal and opposite reaction force. You cannot push on something without it pushing back. If you are floating in mid air and you pull the magnets apart you will not move as the forces cancel out. If you let them pull back together you still will not move and the forces still cancel out. The spaceship around you will not move as it is not connected in any way.If you are attached to the spaceship and one of the magnets is also then when you pull the magnets apart the spaceship will move. Even if the objects you use aren't magnetic and you pull them apart the ship will move. It makes no difference if there is a magnetic field, spring, rubber band or nothing at all. All you are doing is changing the center of mass of the ship by moving the massive objects. All you can do is make the ship wiggle back and forth by a tiny amount as you move the masses apart and back together. All you are doing is shifting the ship with respect to its center of mass. You only have an intuitive grasp of mechanics and your intuition is just wrong. The cannon example shows how bad you have it wrong. The cannon is attached to the Earth so when you fire the cannon in one direction it shoves the entire earth in the other by a tiny amount. When the cannon ball hits the earth it cancels the motion of the cannon and the tiny motion of the Earth. Both are in different positions now. The Earth has moved by only a tiny amount. When you carry the cannon ball back to the cannon you drag the Earth back to its original position as well. In the end everything is back where it started. And just like with the space ship you have only moved the Earth with respect to the center of mass of the Earth ball system. The center of mass did not change at all as the Earth wiggles back and forth.
Quote from: chazemz on 10/16/2017 11:34 amThere are some points to think about. With regard to two magnets attracting each other, could anyone advise me on a situation I am thinking about. I am in a small spacecraft that is positioned 50 meters from a space station that I need to get to. I have no engines and it would appear that my situation is hopeless. I do have a basic understanding of classical physics. On board I have two magnets so I hatch a cunning plan. I fix myself to the spacecraft and fix one of the magnets to myself and pull the other magnet away from the one that is attached to me. I know that the magnets attract with equal magnitude and opposite in direction so the spacecraft will not move (see bootstrapping) when I do this. However when I let the magnet go I can now use this attraction to help me. As the free magnet accelerates towards me, due to third law, I and so the spacecraft will move towards the free magnet, reducing the distance between me and the space station by a tiny amount. If I repeat this process many times I am able to reach my destination with no exhaust. So using classical physics it is easy to achieve what some people believe to be impossible?There are a few ways I can think of to get back to the station using the magnets. If you had a 50m+ string you could throw one of the magnets to the station and hope it attaches. Then you can gently pull yourself towards it. But in the whole process, the center of mass remains stationary. Or, you could throw both magnets in the opposite direction to gain a small velocity towards the station but the center of mass still remains stationary. Or, if you're truly doomed, you could break one of the magnets to make a sharp edge and then poke a small hole in your spacesuit and use the escaping air as a rocket to close the gap yet even then the center of mass remains stationary! But you need to be quick about getting back.
Quote from: ppnl on 10/15/2017 04:25 pmQuote from: chazemz on 10/15/2017 11:21 amGoing back to the thought experiment with the magnets. When I am facing the direction of travel and let go of the magnets, as the magnets accelerate towards each other, does their mass increase?No.You are only converting potential energy into kinetic energy. Thus the energy of the entire system has not changed and so mass has not changed from a relativistic point of view. Which direction you are facing is irrelevant.If you were to let the magnets collide thus converting the kinetic energy into thermal energy and then let that thermal energy radiate away then the mass of the system would decrease. If you were then to pull the magnets apart thus adding potential energy to the system then their mass would increase.In the first instance you are expending energy and storing it as potential energy, so yes.
On a more serious note, By using third law you can use the potential energy of the stretched flux lines as they contract to move an object from within.
The time of the movement is very short but the device overcomes this time constraint.
The rotor arm magnet rotates into the repelling magnet field of the body magnet. As the distance between the two magnets decreases, the repelling force will increase. The repelling force of the body magnet will act upon the rotor arms, causing them to decelerate which can easily be seen on the video. If we apply third law, the rotor arm magnet must therefore apply the same increasing repelling force on the body magnet. This repelling force must therefore restrict the body's attempts to counter rotate.
So there you have it. A very simple device.
Everything that has been explained is known and can be easily accessed. All the information can be easily found on the internet or in any electrical engineering textbook.
I will go through the video in detail :-1) The body is at rest and the nearest tube magnet has been pushed down the tube to allow for starting.2) Power is switched on, the rotor arms accelerate and the body counter-rotates, winding the string.
3) Jerk cycle takes effect, resulting in no counter-rotation of the body.
4) The string now unwinds, so the device swings back and forth (string winding and unwinding) until it returns to its rest position (i.e. string is not wound).
5) Transfer of momentum as observed, device moves in the direction of the rotor arms.
You cannot have things both ways, either classical physics is correct or it is wrong. When I let go of the magnet will I be attracted to it as it is attracted to me?
Quote from: chazemz on 10/18/2017 03:32 pmYou cannot have things both ways, either classical physics is correct or it is wrong. When I let go of the magnet will I be attracted to it as it is attracted to me?Classical physics is correct. You keep describing things contrary to classical physics though.You are the one trying to have it both ways. You want to be attracted to the magnet as it is attracted to you (which you are), but you want to ignore that when you push the magnet away from you, you get pushed back as well. You are applying a force to the magnet greater than the attraction between the 2 magnets to push it away. This means by Newton's third law that it applies an equal and opposite force on you which is therefore also greater than the force of attraction, making you move away as well (to rephrase for clarity, you move in the opposite direction as the direction you pushed magnet).
Quote from: meberbs on 10/18/2017 05:44 pmQuote from: chazemz on 10/18/2017 03:32 pmYou cannot have things both ways, either classical physics is correct or it is wrong. When I let go of the magnet will I be attracted to it as it is attracted to me?Classical physics is correct. You keep describing things contrary to classical physics though.You are the one trying to have it both ways. You want to be attracted to the magnet as it is attracted to you (which you are), but you want to ignore that when you push the magnet away from you, you get pushed back as well. You are applying a force to the magnet greater than the attraction between the 2 magnets to push it away. This means by Newton's third law that it applies an equal and opposite force on you which is therefore also greater than the force of attraction, making you move away as well (to rephrase for clarity, you move in the opposite direction as the direction you pushed magnet).Nice try, you have changed pull to push.
If by pulling the magnets apart I generate a force in the opposite direction, by holding the magnet away from me there would be no opposing force so the spacecraft would glide over to the space station or carry on into the great unknown. How can equal and opposite be greater on one side?
Energy is NEVER irrelevant.
So we can use potential energy with attraction forces to move an object without exhaust.
When the belt magnets are forced into the repelling magnetic fields of the body magnets they will repel with equal and opposite force so the spacecraft will not move. As the belt magnets pass across the hull magnets they will receive a push from the hull magnets and vice versa.
So will the body be pushed back after each interaction
and secondly if we switch the motors off just as the belt magnets pass across the body magnets what will happen?
With the electromagnets we can switch the motors off as the magnets approach one another so causing them to transfer momentum through collision.
Quote from: chazemz on 10/21/2017 10:04 amSo we can use potential energy with attraction forces to move an object without exhaust.No. You have been told this repeatedly, and not acknowledged it. Do you know what the phrase "center of mass will not move" means? Specifically are you even familiar with the concept of "center of mass"?Quote from: chazemz on 10/21/2017 10:04 amWhen the belt magnets are forced into the repelling magnetic fields of the body magnets they will repel with equal and opposite force so the spacecraft will not move. As the belt magnets pass across the hull magnets they will receive a push from the hull magnets and vice versa.You are referring to 3 sets of magnets here, "body" "hull" and "belt" but you only described placing 2 sets, the "hull" and the "belt" for now I am going to assume you that body and hull refer to the same thing, if that is not true, you are going to need to provide a new description that isn't incomplete. (a diagram would help)Quote from: chazemz on 10/21/2017 10:04 amSo will the body be pushed back after each interactionNo, because the forces are equal and opposite. The magnets on the belt which is taut between the wheels transfer the force applied to them to the wheels, which are rigidly connected to the motors which are rigidly connect to the hull, so the hull has equal and opposite forces applied to it and does not move.Quote from: chazemz on 10/21/2017 10:04 am and secondly if we switch the motors off just as the belt magnets pass across the body magnets what will happen?Nothing. The equal and opposite forces would be constant instead of periodic, still nothing would move.Quote from: chazemz on 10/21/2017 10:04 amWith the electromagnets we can switch the motors off as the magnets approach one another so causing them to transfer momentum through collision.How would anything collide? You have not described anything with the freedom of movement to collide with something else.Your entire setup is a Rube Goldberg machine with no apparent purpose other than trying to hide your misunderstanding of physics by making the setup complicated. Rather than changing topic yet again why don't you go back to the situation of just 2 magnets, one attached to you, and one that you push away and then allow it to be attracted back to you. I provided a detailed description of the forces in that situation, and you have not indicated if you understood that post at all.
Quote from: chazemz on 10/21/2017 10:04 amSo we can use potential energy with attraction forces to move an object without exhaust.Sure you can... If the potential energy is with respect to something outside of your device like the gravitational attraction of a planet such as when doing an Oberth maneuver but not internally to your device.
Quote from: Bob012345 on 10/21/2017 04:35 pmQuote from: chazemz on 10/21/2017 10:04 amSo we can use potential energy with attraction forces to move an object without exhaust.Sure you can... If the potential energy is with respect to something outside of your device like the gravitational attraction of a planet such as when doing an Oberth maneuver but not internally to your device.I am in space and am holding the ends of a spring. I PULL on the spring and stretch the spring. The spring applies an equal and opposite force on each hand so I do not move. I let go of the spring. Please, please, tell me and everyone reading this thread that the spring when it is contracting does NOT apply a force on the hand that is holding the one end of the spring.
Quote from: chazemz on 10/21/2017 04:47 pmQuote from: Bob012345 on 10/21/2017 04:35 pmQuote from: chazemz on 10/21/2017 10:04 amSo we can use potential energy with attraction forces to move an object without exhaust.Sure you can... If the potential energy is with respect to something outside of your device like the gravitational attraction of a planet such as when doing an Oberth maneuver but not internally to your device.I am in space and am holding the ends of a spring. I PULL on the spring and stretch the spring. The spring applies an equal and opposite force on each hand so I do not move. I let go of the spring. Please, please, tell me and everyone reading this thread that the spring when it is contracting does NOT apply a force on the hand that is holding the one end of the spring.The force the spring applies to both hands when stretched disappears the instant one hand let's go. Any residual effects that happen due to potential energy stored in the spring and the muscles of both arms won't end up moving the center of mass of the system.
Quote from: Bob012345 on 10/21/2017 05:29 pmQuote from: chazemz on 10/21/2017 04:47 pmQuote from: Bob012345 on 10/21/2017 04:35 pmQuote from: chazemz on 10/21/2017 10:04 amSo we can use potential energy with attraction forces to move an object without exhaust.Sure you can... If the potential energy is with respect to something outside of your device like the gravitational attraction of a planet such as when doing an Oberth maneuver but not internally to your device.I am in space and am holding the ends of a spring. I PULL on the spring and stretch the spring. The spring applies an equal and opposite force on each hand so I do not move. I let go of the spring. Please, please, tell me and everyone reading this thread that the spring when it is contracting does NOT apply a force on the hand that is holding the one end of the spring.The force the spring applies to both hands when stretched disappears the instant one hand let's go. Any residual effects that happen due to potential energy stored in the spring and the muscles of both arms won't end up moving the center of mass of the system.I asked will the contracting spring apply a force to the one hand?
Are you saying that when the motor on the device is switched off the rotor arms do not collide with the body magnet?
The word is PULL. Why do you keep misquoting?
Quote from: chazemz on 10/21/2017 05:50 pmQuote from: Bob012345 on 10/21/2017 05:29 pmQuote from: chazemz on 10/21/2017 04:47 pmQuote from: Bob012345 on 10/21/2017 04:35 pmQuote from: chazemz on 10/21/2017 10:04 amSo we can use potential energy with attraction forces to move an object without exhaust.Sure you can... If the potential energy is with respect to something outside of your device like the gravitational attraction of a planet such as when doing an Oberth maneuver but not internally to your device.I am in space and am holding the ends of a spring. I PULL on the spring and stretch the spring. The spring applies an equal and opposite force on each hand so I do not move. I let go of the spring. Please, please, tell me and everyone reading this thread that the spring when it is contracting does NOT apply a force on the hand that is holding the one end of the spring.The force the spring applies to both hands when stretched disappears the instant one hand let's go. Any residual effects that happen due to potential energy stored in the spring and the muscles of both arms won't end up moving the center of mass of the system.I asked will the contracting spring apply a force to the one hand?The force exists before the spring is let go but not after. So, I believe no, the spring doesn't apply a force to the hand that remains holding it.
Then it's a two body problem, one hand and the spring and the hand that let go. One hand and the spring will move one way < > the other hand will move the other wayBut the centre of mass of the combined system (both hands and the spring) will stay in the same place.
Live empirically! No need to ask people what they think about this. Build a model of the system you are thinking of. It might be suspended above an air table or floating on still water. Use a small radio-controlled actuator to release the end of the spring. Run the experiment and report back to us.
If you are not afraid of simple maths, try reading this, Collisions
Quote from: chazemz on 10/21/2017 04:37 pmAre you saying that when the motor on the device is switched off the rotor arms do not collide with the body magnet?What rotor arms? you didn't describe any rotor arms in your post, and if you are somehow referring to the device that you previously were discussing, you did not state that. Even if that is what you were discussing, there are no collisions between the body and the arms in your device.Quote from: chazemz on 10/21/2017 04:37 pmThe word is PULL. Why do you keep misquoting?I am not misquoting, because I am not quoting you. I am independently describing things using the correct words.You keep saying that you are moving something away from you by pulling it, but as I stated in a previous post, by definition applying a force to move something away from you means pushing it. Pulling it would move it towards you.http://www.dictionary.com/browse/pushhttp://www.dictionary.com/browse/pullYou also completely ignored the questions I asked in the previous post such as: Do you know what "center of mass" means?
If I can offer some advice, if you find yourself stabbed in the stomach do not attempt to pull the knife from your body.
And yes I do know what center of mass means,
What do you know about about second law?
Quote from: nacnud on 10/21/2017 05:55 pmThen it's a two body problem, one hand and the spring and the hand that let go. One hand and the spring will move one way < > the other hand will move the other wayBut the centre of mass of the combined system (both hands and the spring) will stay in the same place.Ermmmmmmmmmmmmmmmmmmmmmmmmmmm............................. no.
Let your spring have mass M1, and the person have mass M2, and at the start let them be at position 0.Then when you release the spring, the spring moves towards the hand holding it, and the body moves in the opposite direction. If the spring is moving at speed v, then the person will be moving in the opposite direction by M1/M2 * v.Their velocities will always be in these proportions. So if when then the hand and spring collide and come to rest the spring is at position x, the person will have moved in the opposite direction by M1/M2 * x.So the center of mass of the whole system will be positioned at M1 * x - M2 * (M1/M2 * x) = 0.
When the spring is stretched, third law applies. When I let go of the spring... The spring now applies a external force to me and I move.
Quote from: chazemz on 10/24/2017 03:41 pmWhen the spring is stretched, third law applies. When I let go of the spring... The spring now applies a external force to me and I move.The spring and you are part of the same system. There are no external forces. The centre of mass of the system does not move.
Quote from: nacnud on 10/24/2017 03:49 pmQuote from: chazemz on 10/24/2017 03:41 pmWhen the spring is stretched, third law applies. When I let go of the spring... The spring now applies a external force to me and I move.The spring and you are part of the same system. There are no external forces. The centre of mass of the system does not move.Are you saying I do not move?
So if when then the hand and spring collide and come to rest the spring is at position x, the person will have moved in the opposite direction by M1/M2 * x.
Also the spring forces are internal, so I am external to the spring. If I am external to the spring, the spring is external to me. When the spring is stretched, third law applies. When I let go of the spring I move a piece on the chess board, nature must respond. The spring now applies an external force to me and I move.If it is a requirement for the jigsaw piece to fit snugly into place with the pieces already laid, then the spring applies an exterior force to me for a short period of time.If the question is "can you move an object without any exhaust" the answer is "yes".
The amount you move is limited by the amount the spring moves, and moving the spring back moves you back:The spring will apply equal and opposite again. If you are suggesting that I move when I move my arms then I can simply do the superman maneuver and go where I please. If you insist on considering the spring as external to you, then the motion of the spring is your exhaust, so no, you are not moving without exhaust.If that is all you have then I am making progress. No, that the centre of mass of you plus the spring does not move.Does my position change?Since we have established that I accelerate, which terminology do you prefer, exterior force or unbalanced force?
Quote from: chazemz on 10/24/2017 04:46 pmThe amount you move is limited by the amount the spring moves, and moving the spring back moves you back:The spring will apply equal and opposite again. If you are suggesting that I move when I move my arms then I can simply do the superman maneuver and go where I please. If you insist on considering the spring as external to you, then the motion of the spring is your exhaust, so no, you are not moving without exhaust.If that is all you have then I am making progress. No, that the centre of mass of you plus the spring does not move.Does my position change?Since we have established that I accelerate, which terminology do you prefer, exterior force or unbalanced force?No. You do not accelerate. Moving your arm shifts a part of you around, but does not move your center of mass. All you are doing is redistributing your mass. Moving your arm back to its original position will return you to your original position. Here is something you can do to understand this concept: Take a pen and a ruler. Remove the cap from the pen so it rolls smoothly. Place the ruler on top of the pen. Imagine this is your spacecraft, with yourself and the springs inside it, and the pen is the center of mass. Shifting your body or the springs is like sliding the ruler to the left. Shifting yourself or the springs back to your original position is like sliding the ruler to the right. But no matter how you move, the spacecraft only shifts around the center of mass.
Quote from: whitelancer64 on 10/24/2017 05:13 pmQuote from: chazemz on 10/24/2017 04:46 pmThe amount you move is limited by the amount the spring moves, and moving the spring back moves you back:The spring will apply equal and opposite again. If you are suggesting that I move when I move my arms then I can simply do the superman maneuver and go where I please. If you insist on considering the spring as external to you, then the motion of the spring is your exhaust, so no, you are not moving without exhaust.If that is all you have then I am making progress. No, that the centre of mass of you plus the spring does not move.Does my position change?Since we have established that I accelerate, which terminology do you prefer, exterior force or unbalanced force?No. You do not accelerate. Moving your arm shifts a part of you around, but does not move your center of mass. All you are doing is redistributing your mass. Moving your arm back to its original position will return you to your original position. Here is something you can do to understand this concept: Take a pen and a ruler. Remove the cap from the pen so it rolls smoothly. Place the ruler on top of the pen. Imagine this is your spacecraft, with yourself and the springs inside it, and the pen is the center of mass. Shifting your body or the springs is like sliding the ruler to the left. Shifting yourself or the springs back to your original position is like sliding the ruler to the right. But no matter how you move, the spacecraft only shifts around the center of mass. Thank you for the reply. I am a little confused. If I am holding the spring in my left hand after it has contracted, does this refer to moving my right hand to my left hand. If so would not the opposite happen if I move my left hand, with spring, to my empty hand. What will happen If I move both hands together at the same time?
The spring will apply equal and opposite again.
If you are suggesting that I move when I move my arms then I can simply do the superman maneuver and go where I please.
Quote from: meberbsIf you insist on considering the spring as external to you, then the motion of the spring is your exhaust, so no, you are not moving without exhaust.If that is all you have then I am making progress.
If you insist on considering the spring as external to you, then the motion of the spring is your exhaust, so no, you are not moving without exhaust.
Quote from: nacnud No, that the centre of mass of you plus the spring does not move.Does my position change?
No, that the centre of mass of you plus the spring does not move.
Since we have established that I accelerate, which terminology do you prefer, exterior force or unbalanced force?
Some people seem to be getting confused by the spring.
We will assume that my center of mass is the middle of my chest. With no spring attached move my arms away from my chest and then return them to their original position.Now consider what will happen when I do so.
Now attach the spring to the middle of my chest and stretch the spring, letting go, and returning my arms to the end of the spring.Now consider what will happen. Since the spring has applied an unbalanced force to me, the result must be different.
Just so I do not misunderstand you. You are saying that as I move my arms away from my body, my body moves away from my arms and when I move my arms towards my body , my body moves towards my arms. Is that correct?
Quote from: chazemz on 10/26/2017 03:12 pmJust so I do not misunderstand you. You are saying that as I move my arms away from my body, my body moves away from my arms and when I move my arms towards my body , my body moves towards my arms. Is that correct?Correct, this is clearly necessary for your center of mass to remain in the same position, and for conservation of momentum.
Since you manage to find a way to misunderstand everything you have been told, I supplied an attached diagram. Your arms move one way, the rest of your body moves the other. The blue line represents the position of the center of mass relative to the horizontal axis. You return to your original position by returning your arms to your sides.Just so I do not misunderstand you. You are saying that as I move my arms away from my body, my body moves away from my arms and when I move my arms towards my body , my body moves towards my arms. Is that correct?
Quote from: chazemz on 10/26/2017 03:12 pmJust so I do not misunderstand you. You are saying that as I move my arms away from my body, my body moves away from my arms and when I move my arms towards my body , my body moves towards my arms. Is that correct?That is absolutely correct. It is somewhat counter-intuitive, because it is at variance with our everyday experience.When you stand on the ground and raise your arms out in front of you, you normally do not detect any movement of your body. That is because friction on the soles of your feet couple you to the planet and so the system that moves back is your body plus the planet. The planet is so much more massive than your arms that the movement is infinitesimal.If you conducted the experiment on a frictionless surface (an air table or ice rink, say) or in space, the effect would be observable if you took care. Your arms account for about 10% of an average body mass, so if you raise your arms out in front of you, you move their centre of mass forward about a foot (half an arm's length). The centre of mass of the rest of your body will move back about one-ninth of that, i.e. just over one inch. The centre of mass of the combined system (arms plus body) won't move at all.(Similarly, your body will move down as you raise your arms - again not observed in everyday experience, because of the forces exerted by the surface of the Earth supporting you)
Quote from: Nick on 10/26/2017 07:10 pmQuote from: chazemz on 10/26/2017 03:12 pmJust so I do not misunderstand you. You are saying that as I move my arms away from my body, my body moves away from my arms and when I move my arms towards my body , my body moves towards my arms. Is that correct?That is absolutely correct. It is somewhat counter-intuitive, because it is at variance with our everyday experience.When you stand on the ground and raise your arms out in front of you, you normally do not detect any movement of your body. That is because friction on the soles of your feet couple you to the planet and so the system that moves back is your body plus the planet. The planet is so much more massive than your arms that the movement is infinitesimal.If you conducted the experiment on a frictionless surface (an air table or ice rink, say) or in space, the effect would be observable if you took care. Your arms account for about 10% of an average body mass, so if you raise your arms out in front of you, you move their centre of mass forward about a foot (half an arm's length). The centre of mass of the rest of your body will move back about one-ninth of that, i.e. just over one inch. The centre of mass of the combined system (arms plus body) won't move at all.(Similarly, your body will move down as you raise your arms - again not observed in everyday experience, because of the forces exerted by the surface of the Earth supporting you) We can now move to the spring. As I pull the spring away from me and stretch it, the spring will resist and apply a force against the movement of my arms and my body.So does my body still move backwards (and if so by how much), applying a ever greater force on the spring and vice versa or is its movement hampered by the increasing potential energy of the spring?
Quote from: chazemz on 10/27/2017 09:21 amQuote from: Nick on 10/26/2017 07:10 pmQuote from: chazemz on 10/26/2017 03:12 pmJust so I do not misunderstand you. You are saying that as I move my arms away from my body, my body moves away from my arms and when I move my arms towards my body , my body moves towards my arms. Is that correct?That is absolutely correct. It is somewhat counter-intuitive, because it is at variance with our everyday experience.When you stand on the ground and raise your arms out in front of you, you normally do not detect any movement of your body. That is because friction on the soles of your feet couple you to the planet and so the system that moves back is your body plus the planet. The planet is so much more massive than your arms that the movement is infinitesimal.If you conducted the experiment on a frictionless surface (an air table or ice rink, say) or in space, the effect would be observable if you took care. Your arms account for about 10% of an average body mass, so if you raise your arms out in front of you, you move their centre of mass forward about a foot (half an arm's length). The centre of mass of the rest of your body will move back about one-ninth of that, i.e. just over one inch. The centre of mass of the combined system (arms plus body) won't move at all.(Similarly, your body will move down as you raise your arms - again not observed in everyday experience, because of the forces exerted by the surface of the Earth supporting you) We can now move to the spring. As I pull the spring away from me and stretch it, the spring will resist and apply a force against the movement of my arms and my body.So does my body still move backwards (and if so by how much), applying a ever greater force on the spring and vice versa or is its movement hampered by the increasing potential energy of the spring?Your body will move backwards more. Now the mass of your arms plus the mass of the spring is extended forward, so your body moves backwards more to compensate. For simplicity, assuming the mass of the spring plus the mass of your arms equals 20% of the total mass, using the rest of the same numbers that Nick did means your body would move backwards a bit more than 2 inches.One thing to keep in mind is that the forces between your hands and one end of the spring are equal and opposite. The forces between the other end of your spring and where it is attached to you are equal and opposite. There is no rule stating that the force on one end of the spring is equal and opposite to the force on the other end of the spring. In fact these have to be unequal at some point to accelerate the center of mass of the spring away from your chest.Intro physics textbooks discussing systems including springs assume massless springs so that the spring itself does not have to be accelerated which is a very good approximation in many practical cases. If we assume the spring in this case is very light compared to your body, then we just get the same final result as without the spring.Note that I did not need to mention energy in this description. It is irrelevant at this point and we can move on to discussing energy once it is not going to just add more confusion.
So, I hold my body in position as I extend my arms.
If I free my body and bring my arms toward me I can transfer the momentum of my body onto another object without the need for me push against anything?
Quote from: chazemz on 10/27/2017 03:51 pmSo, I hold my body in position as I extend my arms.How do you intend to hold your body in position?There is no way to truly do so, except by moving something else in the direction your body would have moved.Quote from: chazemz on 10/27/2017 03:51 pmIf I free my body and bring my arms toward me I can transfer the momentum of my body onto another object without the need for me push against anything?It is unclear what you are trying to say here. Starting from a position with your arms extended and you at rest, pulling your arms towards you will result in your body moving forward slightly ending up stationary with your arms near to your body as we previously discussed. Nothing else happens unless you hit something while making that motion.
So, I hold my body in position as I extend my arms. If I free my body and bring my arms toward me I can transfer the momentum of my body onto another object without the need for me push against anything?
Quote from: meberbs on 10/27/2017 04:11 pmQuote from: chazemz on 10/27/2017 03:51 pmSo, I hold my body in position as I extend my arms.How do you intend to hold your body in position?There is no way to truly do so, except by moving something else in the direction your body would have moved.Quote from: chazemz on 10/27/2017 03:51 pmIf I free my body and bring my arms toward me I can transfer the momentum of my body onto another object without the need for me push against anything?It is unclear what you are trying to say here. Starting from a position with your arms extended and you at rest, pulling your arms towards you will result in your body moving forward slightly ending up stationary with your arms near to your body as we previously discussed. Nothing else happens unless you hit something while making that motion.Substitute my body for the body of the device (stator). Substitute my arms for the field flux lines and read the description again. It would be a good idea to add another magnet onto the belt in the collision scenario of the two counter rotating motors. You are correct read belt instead of body.
Quote from: chazemz on 10/28/2017 09:09 amQuote from: meberbs on 10/27/2017 04:11 pmQuote from: chazemz on 10/27/2017 03:51 pmSo, I hold my body in position as I extend my arms.How do you intend to hold your body in position?There is no way to truly do so, except by moving something else in the direction your body would have moved.Quote from: chazemz on 10/27/2017 03:51 pmIf I free my body and bring my arms toward me I can transfer the momentum of my body onto another object without the need for me push against anything?It is unclear what you are trying to say here. Starting from a position with your arms extended and you at rest, pulling your arms towards you will result in your body moving forward slightly ending up stationary with your arms near to your body as we previously discussed. Nothing else happens unless you hit something while making that motion.Substitute my body for the body of the device (stator). Substitute my arms for the field flux lines and read the description again. It would be a good idea to add another magnet onto the belt in the collision scenario of the two counter rotating motors. You are correct read belt instead of body.I cannot make those substitutions, because they don't make sense. At a basic level a magnetic field does not have mass, while your arms do. Trying to make an analogy there is flawed. There also isn't an equivalent to extending your arms when it comes to magnetic fields.Also, you seem to be switching from a linear motion system to a rotating one.You also have to explain what you mean by "hold the body still" You talk a bout a "device" and "collisions" The device you have shown a video of does not even come close to matching your description here (to start with it only has one motor) and the device you previously attempted to describe involving belts and magnets did not seem to be set up in such a way that a collision could occur. I'd ask for a better description, but most of your descriptions seem to assume that the person on the other end is psychic, so I will have to ask for a detailed labelled diagram.Before moving on to this new system, it would be helpful if you acknowledged the previous description that when stretching a spring attached to you by extending your arms, the spring does not change the result other than increasing the mass of what you extend forward to be mass of arms plus string rather than mass of arms.
You have completely missed the plot here. The spring discussion is neither here or there. To expend so much energy to stop, start, stop, start, a millimetre at a time is, in my opinion, about as useful as a chocolate teapot. The point is to use the scenario and the comments made (thank you to everyone who commented) as a platform to hopefully make some meaningful progress.
If it is your desire for me to be in error
On a completely different subject, using electromagnets in the two counter rotating motor, belt scenario, both the collision and push back instances look cautiously promising.
Basic sketch attached, there are numerous variations that can be made ie change position of hull magnets, add more magnets to belts, add a braking zone per cycle etc, etc, etc.
Before we discuss this situation you still haven't answered an important question: Do you understand that in the scenarios described with stretching a spring that is attached to you, you cannot move anywhere at all no matter how much time or effort you put in?
Your belt magnets are part of the same system as the hull magnets. No motion would occur as the belt magnets would push back with an equal amount of force as the hull magnets. It’s the same reason you cannot lift a manhole cover you are standing on.
Quote from: Basto on 10/31/2017 02:53 pmYour belt magnets are part of the same system as the hull magnets. No motion would occur as the belt magnets would push back with an equal amount of force as the hull magnets. It’s the same reason you cannot lift a manhole cover you are standing on. Remember, the belt magnets are moving and the hull magnets are stationary before the collision occurs.
Quote from: Basto on 10/31/2017 02:53 pmYour belt magnets are part of the same system as the hull magnets. No motion would occur as the belt magnets would push back with an equal amount of force as the hull magnets. It’s the same reason you cannot lift a manhole cover you are standing on.We'll, actually you can in principle but probably impossible in practice..... same as skateboarders lifting the board they ride on. But only because both can react against the earth but the principle behind what I think you meant is correct.
Quote from: Bob012345 on 10/31/2017 03:41 pmQuote from: Basto on 10/31/2017 02:53 pmYour belt magnets are part of the same system as the hull magnets. No motion would occur as the belt magnets would push back with an equal amount of force as the hull magnets. It’s the same reason you cannot lift a manhole cover you are standing on.We'll, actually you can in principle but probably impossible in practice..... same as skateboarders lifting the board they ride on. But only because both can react against the earth but the principle behind what I think you meant is correct. When you turn the motors off, nature is in check. It only has one square to move and that is to transfer the momentum to the body.
The belt magnets and the hull magnets are repelling each other so we will have the facing poles as north. I will go through some scenarios soon, mostly with electromagnets and hopefully someone will have some constructive comments.
Quote from: chazemz on 10/30/2017 04:03 pmThe belt magnets and the hull magnets are repelling each other so we will have the facing poles as north. I will go through some scenarios soon, mostly with electromagnets and hopefully someone will have some constructive comments. Rather than coming up with more complicated contraptions, you would be far better served by taking the time to understand why your previous ideas were wrong. Once you do, you should realize why adding more springs/magnets/belts etc cannot change the basic outcomes, which will save you a lot of time and effort in the long run.As others have suggested, a introductory physics course might help. You might also benefit from spending some time on https://www.lhup.edu/~dsimanek/museum/unwork.htm (spoiler: none of these devices do anything interesting)Nothing you have posted here is "New Physics" (the subject of the forum) or has any novel or interesting implications concerning "Conservation of energy/momentum"
Quote from: hop on 10/31/2017 04:35 pmQuote from: chazemz on 10/30/2017 04:03 pmThe belt magnets and the hull magnets are repelling each other so we will have the facing poles as north. I will go through some scenarios soon, mostly with electromagnets and hopefully someone will have some constructive comments. Rather than coming up with more complicated contraptions, you would be far better served by taking the time to understand why your previous ideas were wrong. Once you do, you should realize why adding more springs/magnets/belts etc cannot change the basic outcomes, which will save you a lot of time and effort in the long run.As others have suggested, a introductory physics course might help. You might also benefit from spending some time on https://www.lhup.edu/~dsimanek/museum/unwork.htm (spoiler: none of these devices do anything interesting)Nothing you have posted here is "New Physics" (the subject of the forum) or has any novel or interesting implications concerning "Conservation of energy/momentum"I am more than happy for you to explain to me where the momentum goes?
I am more than happy for you to explain to me where the momentum goes?
Quote from: chazemz on 10/31/2017 04:48 pmQuote from: hop on 10/31/2017 04:35 pmQuote from: chazemz on 10/30/2017 04:03 pmThe belt magnets and the hull magnets are repelling each other so we will have the facing poles as north. I will go through some scenarios soon, mostly with electromagnets and hopefully someone will have some constructive comments. Rather than coming up with more complicated contraptions, you would be far better served by taking the time to understand why your previous ideas were wrong. Once you do, you should realize why adding more springs/magnets/belts etc cannot change the basic outcomes, which will save you a lot of time and effort in the long run.As others have suggested, a introductory physics course might help. You might also benefit from spending some time on https://www.lhup.edu/~dsimanek/museum/unwork.htm (spoiler: none of these devices do anything interesting)Nothing you have posted here is "New Physics" (the subject of the forum) or has any novel or interesting implications concerning "Conservation of energy/momentum"I am more than happy for you to explain to me where the momentum goes?Assuming you're talking about the magnetic fields, it gets cancelled out by the permanent magnets fixed on the hull. Your magnets are only pushing against each other. The forces involved are balanced, so your spaceship does not travel anywhere.
Quote from: whitelancer64 on 10/31/2017 05:03 pmQuote from: chazemz on 10/31/2017 04:48 pmQuote from: hop on 10/31/2017 04:35 pmQuote from: chazemz on 10/30/2017 04:03 pmThe belt magnets and the hull magnets are repelling each other so we will have the facing poles as north. I will go through some scenarios soon, mostly with electromagnets and hopefully someone will have some constructive comments. Rather than coming up with more complicated contraptions, you would be far better served by taking the time to understand why your previous ideas were wrong. Once you do, you should realize why adding more springs/magnets/belts etc cannot change the basic outcomes, which will save you a lot of time and effort in the long run.As others have suggested, a introductory physics course might help. You might also benefit from spending some time on https://www.lhup.edu/~dsimanek/museum/unwork.htm (spoiler: none of these devices do anything interesting)Nothing you have posted here is "New Physics" (the subject of the forum) or has any novel or interesting implications concerning "Conservation of energy/momentum"I am more than happy for you to explain to me where the momentum goes?Assuming you're talking about the magnetic fields, it gets cancelled out by the permanent magnets fixed on the hull. Your magnets are only pushing against each other. The forces involved are balanced, so your spaceship does not travel anywhere. You need to stop and think. Your problem is not that it works, but if it does not work. The alternative to it not working is to break most laws of physics. When you turn the motors off you decouple the armature from the stator so breaking the normal escape route. You are right in the magnets pushing against each other (they are electromagnets by the way) but the belt magnets have momentum (see collisions), that momentum must go somewhere and we have set up TINA (there is no alternative). As I have said before, if you are going to start the insults at least back them up with some facts. Nailing your feet to the floor and announcing to me that walking is impossible, as I walk past you makes no sense.
The device is enclosed in the box (see diagram) and as I stated earlier, we will add another magnet of the same mass to each belt (all the magnets are electromagnets which at the start are all switched off). The additional magnets will be positioned so that when the motors are switched on, the box will not move. So we switch the motors on and the belts begin to move. When two of the belt magnets are approaching the hull magnets we can switch off the motors and switch on the belt and hull electromagnets. The belt magnets are now able to free wheel towards the hull magnets and since the magnetic orientation is repelling, they collide with the repelling magnetic fields imparting their momentum onto the hull magnets causing the body to move. We do not have to concern ourselves with the slight bounce back. Other configurations ie pull and push back can be considered.