Magnetic fields Definition and 674 Threads

How would it be possible to fluctuate one magnet between two magnets? Thanks

Lets say we have a Direct Current (not an alternating current) going through a wire ; so there is a steady-state magnetic field created around the wire. Then let's say we move some object into the magnetic field that disturbs the field. . My question is : How do we/they get information...

Summary: I need to build an asymmetric capacitor, but the mathematics of electromagnetics become too tough, do you have any info that can help? Appreciate it! Hello, I am an undergraduate student in engineering and I want to build an asymmetric capacitor, so I need electromagnetics which I...

Can anyone explain why an artificial magnetic field may or may not promote an increase in cellular metabolism?

I've had a lot of problems that involve a segment of current carrying wire, for example when you have a square loop of wire. I have a formula for "long" wires that is B = μ0 * I/(2 * π * d). Can I use this for shorter wire segments, and if not, what formula can I use?

Some organisms still have magnetoreceptors, what would be the evolutionary benefits of these receptors?

The videos from Veritasium explaining permanent static magnets and electromagnets were quite good I thought… But they have me a little confused with regard to the origins of magnetic fields generated by an electric current as opposed to a permanent static magnet from say iron. 1. An...

For light it is said it has no volume and also it it waves of electric and magnetic field. But for electric and magnetic field you need space? So can they both be at the same time?

hello, i have a doubt i bought some small neodimium magnets 8x3mm and now i would like to try some experiments with them i have a doubt: if i rotate one of these magnet around one of its parallel axis, very fast , near 1000000 rpm, what happens to the magnetic field produced by the magnet? if...

So I just learned that in general relativity Magnatic and Electric fields are dependent on the observer. What are some consequences as a result?

I have a basic question about magnetic fields, but the answer will help me better understand quantum collapse issues. If the current in a wire is instantaneously shut off, what happens to the magnetic field that was present when the current was flowing? To be more specific: Wire...

I’m looking for a device to produce electromagnetic fields and how can u control the frequency emitted looking to build or purchase looking to experiment any information either reply publicly or inbox me

What happens when magnetic field cancel. Where do they go. Do they just vanish or return to the vacuum? In a GFCI receptacle we have in most of our homes. The sense coil can output zero when there is deviation from net magnetic field between the line and neutral. This means the cancellation...

Suppose a straight current carrying wire is immersed in a uniform electric field along its axis. For this problem, please don't worry about complete loops or return paths, just consider a segment of straight wire carrying a current. Since external electric fields don't get inside conductors due...

Are both magnetic fields emanated from an electromagnet fed with a current spike from a charge capacitor and a rotating static magnetic field from permanent magnets instances of time varying fields? The permanent magnet would be attached to perhaps some rotating disc thus passing over a target...

Homework Statement See picture Homework Equations Dont think so. The Attempt at a Solution I get D, the answer is D. I think it is D because only half a magnetic wave would appear on the inside of the wires as it is a sine wave. If you have more information on answering the question, please...

The reason this is in relativity is ( please correct if wrong )that magnetic fields are effects created by static electricity through length contractions. If a line of electrons move pass a parallel line of positive charges and a charged observer is outside this it would see electrons being...

Homework Statement You observe a molecular cloud core with the following properties: T = 5K R = 1pc M = 10 M⊙ n = 102 cm^-3 B = 1µG RΩ = 200 cms^-1 A. Assuming equipartition of B fields and turbulence, what is the turbulent velocity of the cloud? Homework Equations Emag=1/6((B^2R^3)/μo)...

After reading about Jupiter's magnetic field on ScienceAlert, I remembered another article about tree bark and magnetic anomalies (links below). I also remembered an article on birds being able to see magnetic fields as well. It got me thinking of how and if life is possible on anything other...

I have a question regarding the interactions of electromagnetic fields. Say you have two superconducting electromagnets A and B. The properties of the magnets are known such that you can tell precisely how quickly it takes each one to produce it's full strength magnetic field and how long it...

Very recently, Roger Penrose, along with Daniel An and Krzystztof Meissner, have submitted a new paper to PRL. In the new paper they present new empirical findings which support CCC. It doesn't seem to be out yet though, I can't find it anywhere, but I will place the link here when it is out...

Has anyone ever looked for reversible weight changes while materials are subjected to uniform, strong magnetic fields, such as those involved in nuclear magnetic resonance imaging (MRI) or spectroscopy? I suspect no one ever has, for lack of a reason, and any such effects would have to be...

Homework Statement So I have got the question below. I am asked to find the phase difference between the electric field and magnetic field of electromagnetic waves traveling in a plasma, using the electrical conductivity expression. Now I have found the frequency of the waves and I know that...

Both the gravitational and electric fields associated with matter are centered on the matter itself. However, for a bar magnet, the magnetic field seems to be emanate from discrete loops, only part of which pass through the matter of the magnet. What causes a magnetic field to have this...

Hi, Can anyone direct me to some literature that describes the numerical solution of full Maxwell's equations and Navier-Stokes equations for two-phase/multi-phase flows in coupled electric and magnetic fields. Thanks!

Why does current produce a static magnetic field, but a static magnetic field doesn't produce current? Specifically, why is one true, but the inverse not true? I can accept that each rule individually is just how the universe works... but it sounds so contradictory when I examine both together...

Hi everyone, I am currently working on a project in Physics analyzing the possibility of magnetic fields protecting against radiation particles such as fully ionized nuclei or electrons. I wrote a code in Matlab that simulates a 3-D magnetic field based on a combination of wires and wire loops...

I was recently having a discussion about magnetic fields outside of a shielded power cable. My understanding up to this point was shielded cables only shields electric fields and not magnetic fields which are associated with current flow inside a cable. For the shielding to shield magnetic...

If the speed of light is ~300 m/s in a vacuum, can the electric and magnetic fields of the wave be condensed such that it travels faster? The idea being that an outside force condenses these fields and lenghtens the wavelenght with no loss of energy thus increasing the directional speed. The...

From wikipedia: "An electromagnetic wave such as light consists of a coupled oscillating electric field and magnetic field which are always perpendicular; by convention, the "polarization" of electromagnetic waves refers to the direction of the electric field." A polarizer is an object that...

The sources I've looked at claim the magnetic field is present because there are still some electrons in the neutron star. Here is how I understand their reasoning: a star's radius significantly decreases when it collapses into a neutron star, ultimately decreasing its moment of inertia. In...

Hello! I've made a lot of research about measurement of high magnetic fields - such us 1T - 2T and I can't find sensors for this range. I'm looking for a hall sensor with which I will be able to measure 1T magnetic field with good accuracy - about 0.1 mT. Do you know about anything like that...

1. Why is Earth's South Pole called its North Pole? Why hasn't it been changed to make it more scientifically accurate? 2. Why are the North Poles of other planets defined relative to Earth's 'North' Pole? Why isn't it based upon the actual direction of the planet's magnetic field?

So I know if you move a charge in a magnetic field it induces voltage and hence a flow of charge is created which is current. ( Please correct me if I'm wrong). But that's pretty basic right. However, I'm having trouble understanding the use of split rings in the functioning of a motor. I would...

Is it possible to have a magnetic field of a any geometry we want, or there are only few types of geometries that can be achieved with permanent magnets and electromagnets? If the former, how do we produce a magnetic field of specific geometry? For example, can the magnetic field be cylindrical...

Homework Statement Homework Equations N/A The Attempt at a Solution Im not sure if I've done this right because it seems too little for 6 marks. I have arrows coming from the north to the south end for the magnet's magnetic field. I have arrows going counter clockwise around the conductor...

In a transformer, the primary coil has a current running through it which creates a magnetic field. Then this field induces a current in the secondary coil. That induced current creates a magnetic field exactly opposite the inducing magnetic field. This might be an obvious question, but that...

Homework Statement A proton moves with constant velocity in a certain region of gravity-free space.Which one of the following conclusions is valid? A)There must be no electric field or magnetic fields in the region. B)There could be an electric field without any magnetic field. C)There could be...

I've posted this here because I think it might be related to the absoluteness of acceleration and rotation. I've been educating myself on the Faraday Disk and was very surprised by one aspect of it. If we have a solid metal disk mounted on a shaft with two electrical brushes contacting the...

Hi, I'm currently investigating magnetic fields/their cause. This has inevitably led me to learn all about electrons. Here I want to post my understanding on electron 'spin' so people can correct me if I'm wrong/help others get a better understanding. So I watched this YouTube video for...

I am a teacher and I can't work this one out. I am trying to answer (a). I have only included the further parts of the question (b, c and d) so you can see why some parts of the question are included. A single positively charged particle, mass 4.6 x 1027 kg, enters a 4.0 T magnetic field into...

According to the Einstein field equations, matter and energy both curve spacetime. I'm wondering how magnetic fields contribute to the curvature of spacetime. I have a few questions: 1. Does a magnetic field in a current-free region of a curved spacetime still satisfy Laplace's equation? Or is...

I am studying to about maxwell's equations on the electric and magnetic field. First of all, just do the example and exercise: https://www.princeton.edu/ssp/josep...ide-to-maxwells-equations-D.-FleischLEISC.pdf I have this dipole antenna...

Homework Statement A single ionized uranium ion of mass 6.9 x 10 ^-25 kg is accelerated through a potential difference of 4.4 x 10^5 V. What is the radius of the path it would take if injected at 90 degrees into 0.47 T uniform magnetic field at this velocity? 3. Attempts Since centripetal...

Hi forum, I have been thinking about the circular magnetic field pattern around a long straight current carrying wire and wondering about what the field pattern would be around an isolated electron moving straight in a vacuum? Somehow the magnetic field of all the individual electrons moving in...

Homework Statement How do I find the direction of the magnetic field at the points? Homework Equations Ampere's B = (UI) / (2*pi*r)[/B]The Attempt at a Solution I know how the Right hand rule, where your thumb is the direction of the current and your hand wraps the direction of the field...

Homework Statement A Neutral copper Rod, a polarized insulator rod, and a bar magnet are arranged around a current-carrying wire. Will the neutral copper rod, polarized insulator, and magnet remain stationary?Homework Equations does the electric field of the current carrying wire have an...

Homework Statement Hi, I've got a presentation on an experiment we did using the Helmholtz coil and I'm starting to run dry on material. As some additional applications I found that you can: - Use the coil set up to cancel external interference (Shield other experiments? Not sure about that...

Hi, Can anyone help me in finding out a Diamagnetic or Paramagnetism or Ferromagnetism or any other metal which has following capabilities: 1- Should not be attractive towards magnet. 2- Should not allow magnetic fields to pass through inside. Thanks! THG

I understand that a steady flow of current will not induce currents in near by conductors. But, what about a steady flow of current that is being accelerated perpendicularly by a uniform magnetic field? Wouldn't this current produce a time varying magnetic field? This is a conductive disk with...