Is it not EM drive with a cylindrical chamber, not a conical one?
Keep in mind this is not a free lunch drive. If you believe e=mc^2 and run with it the idea you end with something that can turn energy into thrust. The questions are a) Is this it an b) does this efficiency look reasonable.
It really does promise free unlimited energy. Read my last post. I can expand on the math if you like but there is not much to it.
Quote from: KelvinZero on 11/10/2012 08:27 amIt really does promise free unlimited energy. Read my last post. I can expand on the math if you like but there is not much to it.Please do. Otherwise it comes across as a bald assertion.
.......This is about twice the energy you put in using the propellentless propulsion.Really these numbers do not matter though. The key principle is that the drive lets you increase your velocity linearly with energy, but totally standard physics lets us extract energy out proportional to the square of the velocity.It does not matter if their drive is only a millionth of this effectiveness.. at some point the linear power required will be less than the quadratic curve of the kinetic energy gained.
Quote from: KelvinZero on 11/10/2012 09:17 am.......This is about twice the energy you put in using the propellentless propulsion.Really these numbers do not matter though. The key principle is that the drive lets you increase your velocity linearly with energy, but totally standard physics lets us extract energy out proportional to the square of the velocity.It does not matter if their drive is only a millionth of this effectiveness.. at some point the linear power required will be less than the quadratic curve of the kinetic energy gained.you know that this is not possible with a EM-Drive. If you have read the papers you would know that the performance falls off rather fast with an increase in velocity. An EM-Drive works only good perpendicular to the velocity vector.
Quote from: JohnFornaro on 11/09/2012 02:39 amIs it not EM drive with a cylindrical chamber, not a conical one?"Tapered" cylindrical sounds like a synonym for conical to me.
Ok, it wasn't meant to come across as an assertion but there really isnt much to the math. Numbers are just going to bulk it up.
Now we are agreed that what this means is that for a constant input of power, we get a constant force right?
Quote from: mboeller on 11/10/2012 10:49 amQuote from: KelvinZero on 11/10/2012 09:17 am.......This is about twice the energy you put in using the propellentless propulsion.... The key principle is that the drive lets you increase your velocity linearly with energy, but totally standard physics lets us extract energy out proportional to the square of the velocity.It does not matter if their drive is only a millionth of this effectiveness... at some point the linear power required will be less than the quadratic curve of the kinetic energy gained.you know that this is not possible with a EM-Drive. ... performance falls off rather fast with an increase in velocity. An EM-Drive works only good perpendicular to the velocity vector. Performance falls with velocity relative to what? There is no such thing in physics as absolute velocity.
Quote from: KelvinZero on 11/10/2012 09:17 am.......This is about twice the energy you put in using the propellentless propulsion.... The key principle is that the drive lets you increase your velocity linearly with energy, but totally standard physics lets us extract energy out proportional to the square of the velocity.It does not matter if their drive is only a millionth of this effectiveness... at some point the linear power required will be less than the quadratic curve of the kinetic energy gained.you know that this is not possible with a EM-Drive. ... performance falls off rather fast with an increase in velocity. An EM-Drive works only good perpendicular to the velocity vector.
.......This is about twice the energy you put in using the propellentless propulsion.... The key principle is that the drive lets you increase your velocity linearly with energy, but totally standard physics lets us extract energy out proportional to the square of the velocity.It does not matter if their drive is only a millionth of this effectiveness... at some point the linear power required will be less than the quadratic curve of the kinetic energy gained.
If you believe e=mc^2 and run with it the idea you end with something that can turn energy into thrust. The questions are a) Is this it ?
Shawyer's EmDrive does not have any exhaust. It consists of a tuned cavity shaped like a truncated cone into which resonating microwaves are channeled. Like other radiation, these exert a tiny pressure when reflected off a surface. According to Shawyer, the pressure exerted on the large end of the cavity is greater than the pressure on the small end, producing a net thrust. This appears to be a violation the law of conservation of momentum. However, Shawyer says net thrust occurs because the microwaves have a group velocity (the velocity of a collection of electromagnetic waves) greater in one direction than the other and relativistic effects to modify the Newtonian mechanics.
Performance falls with velocity relative to what? There is no such thing in physics as absolute velocity.
Or perhaps when the Chinese starting fitting them to a habitat and send it to Mars. That would be quite a wake up call.
Quote from: jded on 11/10/2012 11:35 amPerformance falls with velocity relative to what? There is no such thing in physics as absolute velocity.It does not matter what I believe but what is written in the papers about the EM-drive. See for example: http://www.emdrive.com/theorypaper9-4.pdf [page 9]
If you were out in the middle of space, no matter what you weighed, were you to apply0.720 newtons of force, you would accelerate in the opposite direction. If you wanted just to coast at a constant speed, you'd turn off your device. After a given time, if you wanted to decelerate, you'd have to apply 0.720 newtons in the opposite direction. All that energy expelled in starting and stopping is lost to entropy. The benefit that you would have gained would be that you got from Point A to Point B, over a period of time X.You can't get more energy out of the deceleration than you applied during the acceleration.
I believe that it should be theoretically possible to convert energy to momentum.
Now, if it turns out that all this drive does, if it works at all, is give you a terribly inefficient way to turn electrical energy into kinetic energy, leaving conservation of energy in-tact, then that's just not all that interesting from a practical standpoint.Why? Well, you still need a lot of stored energy on-board your vehicle, or you need to receive beamed energy of some sort (such as solar power), which can be converted to electricity to be used.
We already have engines that work in that mode, electric thrusters, and they're much more efficient than the numbers that are coming out of this research (if they're real).
You can't turn electrical energy into kinetic energy without throwing something away. You have to have something to do work on, so it can do work on you in return; you can't do work on yourself. This is blindingly obvious to anyone who understood high school physics....If this is real (which I'm not taking a position on) it needs to be replicated ASAP, because it is huge.
You do understand that these papers are nothing but gobbledegook, right?
What's interesting here is that these Chinese researchers came up with their own theory for how it works, and that new theory is what allowed them to produce a drive that actually works (or so they say).
Now, if it turns out that all this drive does, if it works at all, is give you a terribly inefficient way to turn electrical energy into kinetic energy, leaving conservation of energy in-tact, then that's just not all that interesting from a practical standpoint.
Quote from: JohnFornaro on 11/10/2012 02:39 pmIf you were out in the middle of space, no matter what you weighed, were you to apply0.720 newtons of force, you would accelerate ... if you wanted to decelerate, you'd have to apply 0.720 newtons in the opposite direction. All that energy expelled in starting and stopping is lost to entropy. You can't get more energy out of the deceleration than you applied during the acceleration.Sure you can. All you need to do is fly through an electromagnetic decelerator instead of using the thruster.
If you were out in the middle of space, no matter what you weighed, were you to apply0.720 newtons of force, you would accelerate ... if you wanted to decelerate, you'd have to apply 0.720 newtons in the opposite direction. All that energy expelled in starting and stopping is lost to entropy. You can't get more energy out of the deceleration than you applied during the acceleration.
Then, as you come to a stop at the far end of the decelerator, you plug in and recharge your batteries. IMCAC, if you were doing at least 6945/sqrt(η) m/s or so (where η is the efficiency of the decelerator/charger/battery system), you will be fully charged before the decelerator's caps run dry.
There are better ways; they involve rotation, which is a great way to move fast without going anywhere. Even so, at the reported level of efficiency you do have to go pretty fast...
It's not. They are two different things.
You can't turn electrical energy into kinetic energy without throwing something away...A rocket produces constant thrust at constant power, regardless of how fast it's moving...Cars ... work on something in an external reference frame (ie: the road).
This device doesn't sound like its operating principle should depend on reference frame. It might, if it's actually interacting with a local object like the Earth or the sun, or a lab magnet someone forgot was on the same circuit, or if it interacts with distant matter that's freakishly symmetric, or something like that... Anyway, any device with a frame-independent thrust-to-power ratio, that doesn't throw anything out the back, can be induced to behave like a perpetual motion machine of the first kind.That doesn't mean it is. Mach effect seems to be, at worst, a perpetual motion machine of the second kind, since it does have something to push on and is thus capable of 'farming' energy from the rest of the universe when configured appropriately (thrusters on flywheel hooked to generator, for instance). I'm not sure about this one... I downloaded the paper, but it's in Chinese so I can't read it...
The thrust-to-power ratio in this case is 3472 W/N, which is equivalent to ...
If this is real (which I'm not taking a position on) it needs to be replicated ASAP, because it is huge.
Quote from: 93143 on 11/11/2012 07:37 amYou can't turn electrical energy into kinetic energy without throwing something away. You have to have something to do work on, so it can do work on you in return; you can't do work on yourself. This is blindingly obvious to anyone who understood high school physics.Congratulations catching up with the conversation. Perhaps you could try to not be insulting to those of us who are already here, next time?
You can't turn electrical energy into kinetic energy without throwing something away. You have to have something to do work on, so it can do work on you in return; you can't do work on yourself. This is blindingly obvious to anyone who understood high school physics.
Now, if it turns out that all this drive does, if it works at all, is give you a terribly inefficient way to turn electrical energy into kinetic energy, leaving conservation of energy in-tact
Quote from: 93143 on 11/11/2012 07:37 amQuote from: JohnFornaro on 11/10/2012 02:39 pmYou can't get more energy out of the deceleration than you applied during the acceleration.Sure you can. All you need to do is fly through an electromagnetic decelerator instead of using the thruster. Is this not what the Prius does, when braking downhill? And after your journey over hill and dale, don't you have to fill it up with gas again? Because of entropy?
Quote from: JohnFornaro on 11/10/2012 02:39 pmYou can't get more energy out of the deceleration than you applied during the acceleration.Sure you can. All you need to do is fly through an electromagnetic decelerator instead of using the thruster.
You can't get more energy out of the deceleration than you applied during the acceleration.
Isn't the efficiency term where entropy is factored in?
QuoteThere are better ways; they involve rotation...I don't get what point you are trying to make.
There are better ways; they involve rotation...
Somebody tell me that my summary of the EM Drive, and the ME drive is incorrect: You put electricity into it, and then it moves forward. Note that I don't have the math to prove my belief; I only accept, and that tentatively, what is the topic of this thread: Conversion of energy to forward momentum. I also don't seem to grasp how kinetic energy is apparently not related to momentum.
You can't turn electrical energy into kinetic energy without throwing something away...