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Overcoming magnetic repulsion through linear control

by GhastlyGadgeteer

One of the problems with permenate magnetic motor/generators is that of over coming the initial repulsive force at the start of the power cycle.

I want you to try a little experiment.

Take two 1/4 inch dia magnets and hold them opposite one another so that they repell. You can feel the force they exert on each other when you try to push them closer. OK, nothing new here. Next you will need some steel strips of various thicknesses. Start with a 1/8 inch thick strip and place the magnets on either side so that they repell each other through the steel strip. Depending on the strength of your magnets you may feel a reduction in the force needed to keep the magnets in contact with the steel strip. Now double the thickness of the steel strip and try the magnets again. You might notice that it takes less force to keep the magnets in contact with the steel strip. Keep increasing the thickness of the steel strip until the magnets are both equally attracted to the steel and repulsed by each other, effectively creating a magnetic null.

Now there are two ways one might apply this null towards a working magnetic motor/generator. First you could gradually reduce the thickness of the steel strip along its length so that the magnets start out at the thick end where attraction/repulsion create a null, and become ever more repulsed as they move along the steel strip towards the thinner end. The varying thickness of the steel strip having provided a linear reduction in magnetic shielding with a corresponding linear increase in magnetic repulsive force.

Secondly you could maintain the thickness of the steel strip along its entire length so that the magnetic null extends the full length of the steel strip and then tapper the width of the steel strip so that the magnets become increasingly exposed to one another as they move from the wide end of the steel strip to the narrow end of the steel strip. This again creates a linear increase in magnetic repulsive force.

Do you see how this might be applied to a rotating magnetic motor /generator to ease the transition from low repulsive force at the end of the power cycle and the high repulsive force at the start of the next power cycle?

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Conservation of linear momentum

by GhastlyGadgeteer

Imagine a one ton solid metal sphere hurtling through space at thousands of miles per second. Classic physics tells us that unless affected by external forces the total linear momentum of the sphere cannot change. Damn. We need to stop that sphere dead in its tracks but we have no way of physically interacting with it.

Well I guess we will just have to increase the velocity of all other matter in the universe to match the velocity of our sphere along its vecter effectively making its velocity zero in relationship to the rest of the universe.

Where did its momentum go?

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Hard drive magnets, and the stuff they're mounted to

by phrogg111

So, has anyone pulled apart a hard drive recently?

I did a while back. I heard that hard drive magnets were mounted to a metal that, essentially, blocks the magnetic field from passing through it, in an effort to save the hard drive disks. This may be completely wrong.

From what I understand about these magnets, the poles are arranged quite oddly. On a flat surface, when placed on a table, one side of the magnet is north and the other is south - but they repel each other straight away from the table.

Anyway, the magnets are weird. Hard to describe.

They're attached to these pieces of metal. On the other side of this metal, it is nearly impossible to get the magnets to stick to each other, as if the metal blocks magnetism.

So, my first question is, do hard drive magnets have a material that blocks magnetism, or is this a fancy trick of how the magnets are placed?

My second question: Does such a material exist, able to block magnetism?

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My degree is bigger that yours......

by GhastlyGadgeteer

I was working for an engineering company and was surrounded by engineers who all had at least one BA and there were some with their masters degree. I on the other hand had an AAS in mechanical design and fabrication from a local community college and was still working on my AA in per-engineering at the same college.

I was being lectured by a senior engineer on how little I knew as he was judging from my lack of degrees. He finished by telling me that he was a professional engineer. I on the other hand was a student. I said to him "do you know what the single most important invention is in the whole history of man kind?". He just kind of looked at me and blinked. I said "it is quite arguably the wheel". He shook his head and said, "well, yes, l can see where you are coming from". Then I said " but do you realize that it was invented by someone who had no degree and quite possibly no formal education"?

Never for a moment believe that having a degree somehow compensates someone for a lack of raw intellect.

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Classical Physics

by GhastlyGadgeteer

Yea, we all know what that is. It's that collection of observations turned laws that keeps us from asking too many of the same questions. I like to ask questions, and I don't mind asking a question even if someone else just answered that same question, if that is, I don't agree with the answer.

I once worked with a young just recently graduated mechanical engineer. He had his BA from LSU and was well versed in classical physics. One afternoon he came to me with a problem that he just couldn't solve. "I don't understand, the system is in perfect equilibrium, but the current draw is higher in one direction than the other." I said then it is not in perfect equilibrium. He said "Dave, it's a case of classic physics". I cautioned him not to try to apply textbook answers directly to a real world problem that might have hidden variables. He wouldn't budge. I said, OK. Look at it this way. If there are two children on a seesaw, and they both weigh the same and are equal distances from the folcrum are they in equilibrium? He said, yes, of course they are. I said, OK, now are they moving, or just sitting there? "Just sitting there". I said, that's right. They are perfectly ballanced. Now in your case there is movement so therefore there cannot be equilibrium. His face took on a stunned appearance as he realized that he had fallen victim to dogma.

Never approach a problem thinking that you already know the answer. You don't know what you don't know.

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