# Tag Info

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Yes, there are several different ways to manipulate magnetic fields. One way to shield an area from a magnetic field is to place a highly ferrous material like iron next to the source of the magnetic field. The iron will absorb the field in such a way that the magnetic field would be much smaller on the other side of the iron material. Notice how in this ...

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First off there are many different types of maglev prototypes out there each with their pros and cons. In fact some designs have the drawback of needing shielded compartments for people with pacemakers! However, instead of going into much detail about all the different kinds of magnets that can be used on maglevs, I will try to explain how magnetic fields ...

4

Paradoxically, maybe the home-sized magnetic levitation could be a narrow area, where superconducting solutions could be cheap. I explain, why. Although room-temperature superconductivity is a dream, room superconductivity is not. :-) There are soon superconducting materials which can be cooled by liquid air, and they aren't even costly. Liquid air is ...

3

These are called electropermanent magnets. Source: https://en.wikipedia.org/wiki/Electropermanent_magnet The control can either come from rotating one of the magnets, or by using a control coil. If the magnet is rotated this can change the state of the coil to whether current is needed for the magnet to be on with current or off with current. Can I ...

3

the iron structure(s) inside a generator serve the purpose of minimizing flux leakage, which maximizes the utilization of the magnetic field in generating electricity. One of the ways in which they accomplish this is by furnishing what is called a return path for the lines of force, so as to "close" the magnetic circuit inside the device. For things ...

3

Static electricity is a major issue when handling or dealing with explosives. When blast holes are loaded with ANFO (ammonium nitrate fuel oil) as the main explosive, and a specific density of ANFO is required in the holes, the ANFO is blown into the holes via compressed air and a tube. For short holes drilled with hand held machines, the tube is made of ...

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The current that a generator can produce is limited by the wire used in its construction. At some current level, the I2R losses in the wire will cause excessive heating inside the generator, as well as a voltage drop at the output.

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Not really. Firstly the RA in RADAR stands for RAdio which covers significantly longer wavelengths than the visible light (an in some cases near infra-red) which cameras can detect. While light and radio are both part of the electromagnetism spectrum they are different parts of it and not interchangeable. While they are all part of a spectrum in terms of ...

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There are 2 effects to look out for: Magnetic induction into wiring from e.g. coronal mass ejections. The electrical grid is already largely protected against these events. To protect equipment in your home, unplug it. Radiation damage, in the event that Earth's magnetic field collapses. In computers, this manifests first as Single Event Upsets: components ...

2

That statement about the current being independent of speed is just plain wrong. This should be obvious by thinking about the limiting case. When the generator isn't spinning at all, it won't produce any current, but it will produce current at some finite speed. You can easily prove to yourself that the statement is wrong. Take a simple brushed DC motor. ...

2

Regarding questions 2 and 3, I think you need to look deeper in the chemistry, reactivity, and heat transfer characteristics of Nitrogen. 1) It is not a noble gas. It is reactive, and you benefit from this reactivity each time you eat a plant protein. 2) I have not designed a railgun and I don't have much sense of the thermal inefficiencies here. But I ...

2

The strength of an electromagnet's field will typically be strongest on the inside of the coil (talking about a normal electromagnets). This is true for the geometry of the magnet you've shown in the question. When you run a current through the coil, magnetic fields (perhaps not the best way to phrase this) are produced along the path of the coil that are ...

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Yes, but it's unlikely. Damage from other frequencies will be limited because typical receivers have a pre-select filter after the antenna to filter out other frequencies. In band signals pass through a Low Noise Amplifier (LNA) directly after the antenna, which can saturate if the signal level is high, and fail if the signal level exceeds its maximum input ...

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It looks like it should work. It is a little more geometry specific than you are thinking, so I have modified your design below. It will require a reasonable amount of experimentation to perfect the correct permanent magnet strength, required current, and distances to match the surface tension of mercury, etc. Other things that would need to be tested ...

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Yes they can and they are in use. Details on Wiki By Sebastian Terfloth User:Sese_Ingolstadt - Own work, CC BY-SA 3.0 A linear eddy current brake in a German ICE 3 high-speed train in action.

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There's very little data available to evaluate these claims. The manufacturers tend to rely on anecdotal information and testimonials rather than hard data, and no-one else really has any incentive to spend money to test these devices. I did find an article from Penn State University that cites several studies which reported no effect from the devices, and ...

2

To make sure the inductor will respond that fast, you need to solve for the size of the inductor (which will make your magnetic field) which will be resonant at 1000Hz when coupled with a capacitor of convenient size. luckily, an old-school stereo speaker containing a woofer and a midrange speaker will contain a crossover network which has in it an ...

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You should be able to find a picture on the web, but -- yes. One is north on the inside and south on the outside, the other is south on the inside and north on the outside (so pay attention if you have a pile of taken-apart motors that you're reassembling!). The steel can of the motor helps to convey the flux between the outside poles of the magnets, which ...

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It’s a pointless design since all you do is decrease the amount of magnetic coupling between the rotor and stator. You may as well just reduce the current - it’ll have the same effect. You’d have to explain why you think that a wildly varying load would somehow benefit from having less of a motor available (when the rotor is not all the way in). What sort of ...

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Reading a magnetic field with a laser or other light source will be "difficult" because light is not charged and it does not have its own magnetic field.... except it is electromagnetic radiation. I will speculate that it is "science fictionally possible" to affect the phase of a laser with a rapidly (~10^14 Hz) changing magnetic field but that is not going ...

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Actually if you can run the wire through the tube there is a simpler method. Send a radio signal through the wire and use a detector tuned to that signal. This requires some specialized equipment though. If the tube was buried recently there may be a tracer wire already next to it you can use for this.

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Your "best" options would be waterjet or laser cutting as long as the cutting tolerances are acceptable for your design. There are virtually no tooling costs. You can make a 2D cad drawing and get multiple quotes very quickly for this type of manufacturing. Otherwise, continuous die cutting/stamping from a foil roll would be more suited for high volume, ...

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An induction heater creates an oscillating magnetic field near the coil. The "mechanism" to damage an electronic component is that eddy currents are induced in the metal parts of the component. These eddy currents heat up the part until something breaks. If the part breaks, yes, it will be due to magnetic induction.

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No. Stating the obvious, a line of sight (LOS) system won't detect things below the horizon. Now, if atmospheric conditions cause a waveguide effect, signals could propogate farther (and back), but that means intermittent dropouts at best. In addition, since that signal path includes an unknown number of bounces (reflections), the true distance is rather ...

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ELF will likely be very problematic for you practically; remember that your antenna will have to be on the order of a wavelength to transmit or receive such a signal. Even for a 1/4 wavelength antenna, a 30 Hz antenna is 2500 km long. ULF has some history of amateur radio use, so at least it is feasible - and there are commercial antennas made by Aaronia ...

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Look up ERW ( electric resistance welding ) , this is commonly used to weld steel pipe and tubes ( not necessarily round). Spot welding and projection welds have similar aspects.

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Your goal is to move the electrons in a neuron with a magnetic field. If we assume a homogeneous magnetic field $\mathbf{B}$, then this will generate an electrodynamic force $$\mathbf{F}=q\mathbf{v}\times\mathbf{B},$$ that acts on a charge $q$ which moves with the velocity $\mathbf{v}$. If we move the magnet from orthogonal to the direction of the neuron-...

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A carbon nanotube is a conductor. It is somehow a 'rolled graphene sheet' and the material graphite (stack of graphene layers) is quite a famous conductor. What characterize the carbon nanotube is its 'fairly' good strength, together with a ballistic conduction. Therefore as for any conductor, the equation emf = B.L.V is perfectly valid (the equation ...

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