Will a Magnetic Induction Engine work?

[Johnny5]

The appropriate category for this is classical electrodynamics, but there is no category here for that. But since relativity comes out of EM, I figured I would put it here. My question is quite simple.

 

I want to know if this propulsion system will work or not.

 

Construct a solenoid. Wrap a wire around a cylinder N times. Now place an iron ring around the solenoid, and then connect the leads to a battery. There will be an induced EMF in the iron ring, and the ring will be launched into the air. Jumping ring demonstration. So something is pushing that ring up, in the rest frame of the solenoid.

 

Ignoring action/reaction for the moment...

 

Suppose you connect the ring to the cylinder using a dielectric, and then turn on the current. Now, the force is transmitted to the solenoid, not just to the iron ring. If that force exceeds the weight of the ring, solenoid, and battery, the whole system can rise into the air.

 

The formula for the magnetic field of a solenoid is, to a good approximation:

 

B= m N I

 

Where mu is the permeability of free space (which is a constant of nature)

N is the number of times we wrapped a wire around a cylinder

I is the electric current in the wire

 

We can easily control B since we can easily control N, and I.

 

The current would have to be huge in order to do this, but perhaps in the future, a superconductive wire will be found, which can sustain huge electric currents.

 

So can a superconductive solenoid propel us through the vacuum?

[Guest Dieleman]

Doesn't the action/reaction principle apply to magnetics? It's like trying to lift yourself up by your feet?

[swansont]

Doesn't the action/reaction principle apply to magnetics? It's like trying to lift yourself up by your feet?

 

Yes.

[Johnny5]

Doesn't the action/reaction principle apply to magnetics? It's like trying to lift yourself up by your feet?

 

There are problems in electrodynamics, in which Newton's third law is violated... is one of them? <------ THAT'S THE WHOLE QUESTION.

 

I was hoping to get more responses, but no one here wants to take this on. That's a shame.

 

You are in space. Your spaceship is twenty feet away from you to your left, and at rest relative to you. You have in your posession a cylinder, copper wire, a battery, and an iron ring, they are parts of your jetpack which broke. You have 10 minutes left of oxygen, and there's no one on the ship to help you. What do you do?

[Klaynos]

There are problems in electrodynamics' date=' in which Newton's third law is violated... is one of them? <------ THAT'S THE WHOLE QUESTION.

 

I was hoping to get more responses, but no one here wants to take this on. That's a shame.

 

You are in space. Your spaceship is twenty feet away from you to your left, and at rest relative to you. You have in your posession a cylinder, copper wire, a battery, and an iron ring, they are parts of your jetpack which broke. You have 10 minutes left of oxygen, and there's no one on the ship to help you. What do you do?[/quote']

 

 

I take each part of my jet pack and apply "rocket motion", which bassically means I eject mass, so I throw my jet pack away as hard as I possibly can away from the space ship, this results in me moving towards the ship due to conservation of momentum

 

The system you consider above in your first post I belive relies on you placing it on top of system, it then "jumps" and "pushes" itself from whatever it is placed on, so if you where to do it in space holding onto it it would have no effect, if you did it in space touching nothing it would have no effect overall, the only reason it has an effect on earth is ebcause the earths mass is so large compared to it and it is not fixed to the earth. I think...

[Johnny5]

I take each part of my jet pack and apply "rocket motion"' date=' which bassically means I eject mass, so I throw my jet pack away as hard as I possibly can away from the space ship, this results in me moving towards the ship due to conservation of momentum

 

The system you consider above in your first post I belive relies on you placing it on top of system, it then "jumps" and "pushes" itself from whatever it is placed on, so if you where to do it in space holding onto it it would have no effect, if you did it in space touching nothing it would have no effect overall, the only reason it has an effect on earth is ebcause the earths mass is so large compared to it and it is not fixed to the earth. I think...[/quote']

 

That violates the spirit of the problem you know. Your jetpack is connected to your spacesuit, and if you throw it you will tear a hole in the suit.

[J.C.MacSwell]

There are problems in electrodynamics' date=' in which Newton's third law is violated... is one of them? <------ THAT'S THE WHOLE QUESTION.

 

I was hoping to get more responses, but no one here wants to take this on. That's a shame.

 

You are in space. Your spaceship is twenty feet away from you to your left, and at rest relative to you. You have in your posession a cylinder, copper wire, a battery, and an iron ring, they are parts of your jetpack which broke. You have 10 minutes left of oxygen, and there's no one on the ship to help you. What do you do?[/quote']

 

Push some of that junk hard to your right!

[Klaynos]

That violates the spirit of the problem you know. Your jetpack is connected to your spacesuit, and if you throw it you will tear a hole in the suit.

 

just throw away the parts you've taken out, depending on their mass you might be able to make it in 10 mins

[Johnny5]

Push some of that junk hard to your right!

 

 

Yes I seem to be getting this answer a lot.

[Johnny5]

Your backpack is permanently connected to your suit, and it happens to contain a solenoid, which is permanently connected to it. You have a space-tool which is a ring in shape, which just happens to fit around the solenoid, and some space-tape, so you can tape the ring to the solenoid if you wish. You have a switch which can turn the battery to the solenoid on or off, attached to a guage.

 

So the only thing you can throw, is the ring.

 

The mass of the ring is such that if you throw it with your maximum force, you will reach the ship in 11 minutes, so that's out. What do you do?

 

 

PS: The tape is effectively massless.

 

[swansont]

I was hoping to get more responses' date=' but no one here wants to take this on. That's a shame.

[/quote']

 

Spare me. Nobody here is obligated to answer any questions. People have been quite willing to help you, and I think it's bad form for you to chastize anyone.

 

It gets a little tiring when you ask a question that seems to be merely a setup to some other tangential discussion. You obviously had some other topic in mind.

[[Tycho?]]

Doesn't the action/reaction principle apply to magnetics? It's like trying to lift yourself up by your feet?

 

Yes it does, and yes it is.

 

I've never heard of anything like this, and would bet that such a setup could not levitate that way, because, whats it levitating against?

[Janus]

Your backpack is permanently connected to your suit' date=' and it happens to contain a solenoid, which is permanently connected to it. You have a space-tool which is a ring in shape, which just happens to fit around the solenoid, and some space-tape, so you can tape the ring to the solenoid if you wish. You have a switch which can turn the battery to the solenoid on or off, attached to a guage.

 

So the only thing you can throw, is the ring.

 

The mass of the ring is such that if you throw it with your maximum force, you will reach the ship in 11 minutes, so that's out. What do you do?

 

 

PS: The tape is effectively massless.

 

[/quote']

 

You lose the tape, point the solenoid towards the ship, hope that the ship is ferromagnetic and that the solenoid is powerfull enough to pull you to the ship in under 10 min.

 

Or, you could wrap some tape around the ring, sticky side out, Leaving your self about 20 ft of lose tape(folded in half lenghwise so it won't stick to itself) or conversely, unwind about 20 ft of wire from the solenoid. Gently toss the ring towards the ship, and hope that it adheres to the ship stongly enough to allow you to pull yourself to the ship in less than 10 min. (assuming you and your suit mass about 100kg, then that adhesion would only have to resist about .0033 Newtons)

 

But if you are hoping to build some reactionless drive with this stuff that will move you to the ship, then you're betting on a dead horse and will soon be dead yourself.

[Johnny5]

Spare me. Nobody here is obligated to answer any questions. People have been quite willing to help you' date=' and I think it's bad form for you to chastize anyone.

 

It gets a little tiring when you ask a question that seems to be merely a setup to some other tangential discussion. You obviously had some other topic in mind.[/quote']

 

What I really want to know is whether or not Newton's third law holds in this case.

 

Consider the jumping ring demonstration, there are videos of it on the web.

 

You can't see anything, other than the ring soaring upwards.

You cannot see what is pushing the ring up.

Whatever is interacting with the ring, isn't connected to the solenoid when it interacts with the ring. So it's not immediately clear to me anyways, that there is a reaction force down on the solenoid.

 

I've never done the experiment myself, and it's a simple one to do. In fact one could do it in the space shuttle, and immediately know the answer.

 

Connect the ring to a solenoid, let the apparatus float in the cargo bay.

Then turn on the current.

 

Either the whole apparatus will accelerate relative in the cargo bay, or not.

 

So which is it?

 

I personally don't know the answer, but since the question is empirical, I figure someone already knows.

 

Giant supercolliders use the technology, so what's the answer?

[Janus]

What I really want to know is whether or not Newton's third law holds in this case.

 

Consider the jumping ring demonstration' date=' there are videos of it on the web.

 

You can't see anything, other than the ring soaring upwards.

You cannot see what is pushing the ring up.

Whatever is interacting with the ring, isn't connected to the solenoid when it interacts with the ring. So it's not immediately clear to me anyways, that there is a reaction force down on the solenoid.

 

I've never done the experiment myself, and it's a simple one to do. In fact one could do it in the space shuttle, and immediately know the answer.

 

Connect the ring to a solenoid, let the apparatus float in the cargo bay.

Then turn on the current.

 

Either the whole apparatus will accelerate relative in the cargo bay, or not.

 

So which is it?

 

I personally don't know the answer, but since the question is empirical, I figure someone already knows.

 

Giant supercolliders use the technology, so what's the answer?[/quote']

 

The answer is this. When you turn on the solenoid, it induces eddy currents in the ring. These electrical currents turn the ring itself into a magnet which is repulsed by the magnetic field of the solenoid. This is shown by the fact that the more conductive the ring, the higher it will jump and that if the ring is not complete, it will not jump.

 

The jump is caused by simple magnetic repulsion, and the ring repels the solenoid just as much as the solenoid repels the ring. They push against each other. If you were to place them floating in space, the ring would fly in one direction and the solenoid would recoil in the other.

 

You don't even have to go out into space to demonstrate this, just place the solenoid on a sensitive scale and note how the scale registers an increase of weight when the ring jumps off and the scale absorbs the force of the solenoid's recoil.

[Johnny5]

The answer is this. When you turn on the solenoid' date=' it induces eddy currents in the ring. These electrical currents turn the ring itself into a magnet which is repulsed by the magnetic field of the solenoid. This is shown by the fact that the more conductive the ring, the higher it will jump and that if the ring is not complete, it will not jump.

 

The jump is caused by simple magnetic repulsion, and the ring repels the solenoid just as much as the solenoid repels the ring. They [i']push against each other[/i]. If you were to place them floating in space, the ring would fly in one direction and the solenoid would recoil in the other.

 

You don't even have to go out into space to demonstrate this, just place the solenoid on a sensitive scale and note how the scale registers an increase of weight when the ring jumps off and the scale absorbs the force of the solenoid's recoil.

 

Ok then a followup question. Does classical EM predict this?

[Janus]

Ok then a followup question. Does classical EM predict this?

Yes.

[Johnny5]

Originally Posted by Johnny5

Ok then a followup question. Does classical EM predict this?

 

Yes.

 

Alright then lets go slowly, because I have a chance to learn something apparently. Firstly, can you provide a proof for me, that classical EM predicts this. And secondly, I read that certain problems in classical EM exhibit a breakdown of Newton's third law. I would like to see such an example. I remember reading about the Larmor formula, and in my book, there was a comment about something reacting before a force was exerted. I think that alone would demonstrate a third law violation.

 

If you don't have the time to answer, then you needn't. It's just that I really would like to finally understand this.

 

Thank you