Fields Definition and 1000 Threads

The Faraday paradox is a hard one to get ones head around and I was wondering if there is a similar scenario, involving an E field where there is / or is not an induced emf?

Discharging a capacitor through an inductor creates oscillations. This is about as much as I understand about it. I'm having a hard time explaining my question so I attached a pic. My questions: 1. In circuit A, are there oscillations in the inductor as the battery charges the first capacitor...

I am 15 and in high school and recently there has been a big push in our school system to decide on your career now. For the past 7 years I have had it in my mind to become a nuclear physicist. Now, however, I can not decide on what physics field to go into. I can not choose between nuclear...

Hello! (Wave) Given the following two lists: what could we do, so that the first list contains both the elements of the first and the second list, sorted? (Thinking) I wrote the following algorithm: pointer *P=L1, *Q=L2,n; while ((P != '\0') && ( Q != '\0')){...

So there was this article published today that some researchers may have found a dark matter signature emanating from the sun in the form of xr-ray emission from axion interactions with Earth's magnetic field. Article...

If a question asks for the direction of the maximum gradient of a scalar field, is it acceptable to just use del(x) as the answer or is the question asking for a unit vector? Thanks

How would you generate extreme electric fields between two small surface area parallel plates.

If we consider a current carrying conductor, every instant an electron enters the conductor, another electron will be leaving the conductor. Thus, the current carrying conductor will not be charged (i.e, it would not have any net positive or negative charge). Remember dipole has zero net charge...

Dear all! I think the main difference between scalar and vector fields is that vectorial fields are composed of vector elements that varies among them. Scalar fields are fields that have large regions of equal magnitude, variations are just presented in different regions. Please bring me help...

Homework Statement a. Calculate the energy density of the electric field at a distance r from an electron (presumed to be a particle) at rest. b. Assume now that the electron is not a point but a sphere of radius R over whose surface the electron charge is uniformly distributed. Determine the...

I'm limiting my question to this field because it is the only one I know of with a certain degree of knowledge. I doubt they really exist because of the following reasoning: Coulombs law was stated because it makes mathematical sense (think of "force directly proportional to the charges and...

The time I will be asked to take a subject for my graduation project and I'm searching for something in hot fields for modern physics research. Unfortunately I don't know where to look and I was hoping for some help. Any suggestion would be much appreciated. Thank you in advance.

Hello PF, I am having a bit of difficulty understanding this question. Homework Statement "A thin wire with linear charge density λ is surrounded by a conducting cylindrical shell." (There is a hollow cylinder with a wire though it) "If the electric field must be zero inside a conductor, is...

Quantum field theory deals with the quantization of the electro-magnetic field, and finds its quantum: the photon. Electric and magnetic fields are classical fields. Can QFT quantize also them, and find their quanta? It is often said the electrons are field quanta (particles are quanta)...

One argument against Mach's principle is the speed of light restriction. How could the distant cosmic mass of the universe instantaneously have a local effect on an accelerating mass? But could we view this from the perspective of a field that is already presently locally at all points in...

Hi All, I am going over a definition of a Contact Vector Field defined on a 3-manifold: this is defined as " a vector field v whose flow preserves the contact structure " . 1) Background (sorry if this is too simple) A contact structure ## \xi ##( let's stick to 3-manifolds for now ) is a...

Hello. I'm looking to build a strong electro magnet with ac power. I was going to use a MOT transformer so the primary was going to be the same windings. For the secondary windings though I'm trying to decide if I want to go with a higher current or voltage. I would assume that a stronger...

Homework Statement A plastic rod of finite length carries an uniform linear charge Q = -5 μC along the x-axis with the left edge of the rod at the origin (0,0) and its right edge at (8,0) m. All distances are measured in meters. Determine the magnitude and direction of the net electric...

Two electrons, they have their electric fields and magnetic dipole moments. Their electric field is proportional to 1/r^2, and electric force is also proportional to 1/r^2. http://en.wikipedia.org/wiki/Magnetic_dipole%E2%80%93dipole_interaction However, their magnetic dipole field is...

So, as i understand, the geometrical meaning of this type of integral should still be the area under the curve, however, I really do not see how you can obtain each infinitesimal rectangle from the dot product. I have understood the typical work example, that is, the line integral as the sum...

Do gauge fields work the same way as the Higgs field? Are gauge fields all encompassing too, like the Higgs field? What are the differences between the functioning of gauge fields and Higgs field?

I know that a magnetic field will have an electric field bc there is charges, and they are moving. Thanks physicsforums!

Hi I am in a debate with some creationists. They are claiming that the speed of light changes in strong gravitational fields and can be slower or faster. My view is there can be time dilation effects. For example light towards the centre ( a black hole ) will be red shifted, and away from...

For a science fair experiment me and my partner created plasma using a microwave. We used two different methods which both had different results. For the first one we simply put a match on a raised surface and put a beaker over the top using small pieces of cork to elevate the blacker so that...

A gauge field W_\mu is known to transform as W_\mu\to W'_\mu=UW_\mu U^{-1} +(\partial_\mu U)U^{-1} under a gauge transformation U, where the first term UW_\mu U^{-1} means it transforms under the adjoint representation. Can anyone explain to me why it means a transformation under the adjoint...

1) Do all conservative fields follow Gauss's Law? For all laws of the nature 1/R^n the field would be conservative but would follow Gauss's Law only when n=2. So a field may be conservative but would not follow Gauss's law? 2) Do all field that follow Gauss's Law conservative in nature? Are...

Hello all. I am currently studying electromagnetism with Griffiths' books, and I have already donde electrostatic and magnetostatics. Now I am reviewing Ohm's law en emf concepts, but I have a doubt: In griffths book, when explaining ohm's law and emf, it seems to me that he assumes...

Comets have what is called an "induced magnetosphere". Has anyone been able to document polarity in any of the observed comets magnetic fields yet ? If they have I'm curious how it relates to the orbital plane of the comet. I haven't been able to locate that info if it exists so just...

Good to see mathematics hitting the headlines this morning, with news of the first-ever female Fields medallist.

http://www.slate.com/blogs/the_slatest/2014/08/12/first_female_fields_medal_winner_maryam_mirzakhani_of_stanford.html Stanford Report, August 12, 2014 http://news.stanford.edu/news/2014/august/fields-medal-mirzakhani-081214.html Stanford's Maryam Mirzakhani wins Fields Medal Maryam...

Why are magnetic fields and electric fields still considered different phenomena? Doesn't relativity and QFT explain that they are the same thing. A photon is a photon, isn't it? I mean, what is happening when two magnets repel? They exchange photons. What happens when two electrons repel? They...

Homework Statement Calculate the magnitude and direction of the electric field at point Z in Figure 13, due to the charged spheres at points X and Y. Homework Equations E = kq1/r^2 The Attempt at a Solution Determine each vector component: Ex = (9.0x10^9 Nm^2/C^2)(50.0 x...

does anyone have a proof of this?

Homework Statement ##\nabla{F} = <2xyze^{x^2},ze^{x^2},ye^{x^2}## if f(0,0,0) = 5 find f(1,1,2)Homework Equations The Attempt at a Solution my book doesn't have a good example of a problem like this, am I looking for a potential? ##<\frac{\partial}{\partial x},\frac{\partial}{\partial...

Consider an equilateral triangle of side 15.6 cm. A charge of +2.0uc is placed at one vertex and charges of -4.0C uc each are placed at the other two, as shown in the diagram to the right. Determine the electric field at the centre of the triangle ANgle= 60 sides--> d1= d2=d3=0.156m...

I am reading Beachy and Blair's book: Abstract Algebra (3rd Edition) and am currently studying Section 6.5: Finite Fields, I need help with a statement of Beachy & Blair in Example 6.5.2 on page 298. Example 6.5.2 reads as follows:https://www.physicsforums.com/attachments/2858In the above...

I am reading Beachy and Blair's book: Abstract Algebra (3rd Edition) and am currently studying Theorem 6.5.7. I need help with the proof of the Theorem. Theorem 6.5.7 and its proof read as follows:In the above proof, Beachy and Blair write: By Lemma 6.5.4, the set of all roots of f(x) is a...

I am reading Beachy and Blair's book: Abstract Algebra (3rd Edition) and am currently studying Proposition 6.5.5. I need help with the proof of the proposition. Proposition 6.5.5 and its proof read as follows: In the proof of Proposition 6.5.5 Beachy and Blair write: " ... ... Since F is the...

I am reading Beachy and Blair's book: Abstract Algebra (3rd Edition) and am currently studying Theorem 6.5.2. I need help with the proof of the Theorem. Theorem 6.5.2 and its proof read as follows:In the conclusion of the proof, Beachy and Blair write the following: " ... ... Hence, since F...

i am studying finite fields and trying to get an idea of the nature of finite fields. In order to achieve this understanding I am bring to determine the elements and the addition and multiplication tables of some finite fields of small order. For a start I am trying to determine the elements...

anyone know how to do it? how to graph differential equations along with the slope/direction field? (Wondering)

I am reading Section 6.4: Splitting Fields in Beachy and Blair: Abstract Algebra. I am currently studying Example 6.4.2 on page 290 which concerns the splitting field of x^3 - 2 \text{ over } \mathbb{Q} . In Example 6.4.2, B&B show that the splitting field of x^3 - 2 \text{ over }...

https://www.physicsforums.com/showthread.php?p=2881300#post2881300 According to the quoted thread above and according to textbooks and Wikipedia the phase between the E and B fields of an electromagnetic wave propagating in free space is zero. This assertion is based on the Maxwell equations...

Hi all, I am looking into induced electric fields by changing B fields inside layers of dielectric. For example, if a block of several layers of a dielectric material is placed inside a capacitor plate, the E fields inside each layer is shielded depending on the relative permitivitty...

I am wondering if it is possible to shield strong (1 Tesla) DC magnetic fields with high attenuation factor (10^4 or better) WITHOUT also shielding AC magnetic fields above frequencies of ~10kHz. I have looked at mu-metal, which as far as I can tell shields DC but also AC fields to some...

Hi guys! I was wondering if someone could me help to get a free electronic copy of R. Wangsness book "Electromagnetic Fields". I would like to point out that I am just looking for a book which does not violate copyrights.

Help required to understand the physics concepts What will be produced if mutual induction of electric and magnetic fields occurs? Thanks

Hello. I was going through the problems in the angular momentum chapter of the text "Problem Book in Relativity and Gravitation"-Lightman et al in preparation for a project and I came upon part (c) of problem 11.10. It basically starts with a family of observers with 4-velocity ##u^{\mu} =...

I am reading Joseph Rotman's book Advanced Modern Algebra. I need help with Problem 2.34 on page 101. Problem 2.34 reads as follows: -------------------------------------------------------------------- Prove that any two fields having exactly four elements are isomorphic...

E = - grad*phi - 1/c (dA/dt). phi is the scalar potential, and is given. How do I calculate the vector potential = A ? Is it A = (v/c) * phi ? If it is, then where is this equation coming from? Thank you.