Electric Definition and 1000 Threads

I used the equation below and the attachment to rationalize. https://www.physicsforums.com/attachments/282163

So I was wondering, can a moving electric field produce a drag force on gas for example similar to that which would result from physical blades moving the gas. Electric field applied to a dielectric if not as strong as to produce breakdown produces polarization. I wonder can this polarization...

Please help me on this question I have tried to do it many times but I end up getting the wrong answers. I have show my work what I have done.

taking origin at the centre of the square. ##d\phi = \vec E.\vec{da}## $$d\phi = \frac {kqa}{(x^2 + y^2 + a^2)^{3/2}} da$$ $$\phi = \int_{-a/2}^{a/2}\int_{-a/2}^{a/2}\frac{kqa}{(x^2+y^2+a^2)^{3/2}}(dx)(dy)$$ on evaluating this double integral i get $$\phi = (q/\pi{\varepsilon}_0...

I am trying to work out the co-rotating electric potential ##\Phi = \xi^{\mu} A_{\mu}## for the KN solution. First it's necessary to prove that the hypersurfaces ##r = r_{\pm}## are Killing horizons ##\mathcal{N}_{\pm}## of a Killing field of the form ##\xi = k + \Omega_H m## for some Killing...

I tried to find the charge distribution using the given potential but couldn't produce the correct result. Also, Gauss's Law doesn't help, as the electric flux is 0 but we don't have any symmetry. Can someone please shine a light on this? Thanks in advance..

I have encountered two (?) definitions of the electric quadrupole moment. They are: $$Q_{ij}=\frac{1}{2}\int \rho(\vec{x}')x'_i x'_j\,\mathrm{d}^3x'$$ and $$Q_{ij}=\int (3x'_i x'_j-\delta_{ij}x'^2)\rho(\vec{x}')\,\mathrm{d}^3x'$$ I am trying to study radiation arising from the electric...

Summary:: The image shows two circuits, in the first one, using Nodal Analysis we find that V1=4.8V, but in the second circuit V1=10 because using KCL - 10+V1=0. I understand what happened in the first circuit, but I don't understand what happened in the second one, they look the same to me...

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This the photo of my textbook, Here In the derivation of Electric Field Intensity due to an infinitely long straight uniformly charged wire - In the figure 1(c).20 Vector E1 and vector E2 are electric fields at point P due to the two line elements as shown in the figure 1(c).20. But, in this...

I am reading Griffith's textbook on EM. There is a problem asking to find the force acting on the northern hemisphere by the southern hemisphere of a uniformly charged sphere. The solution idea is to find the expression of the E field by Gauss's law and integrate the force over the northern...

Hi. How does the charge ##q## relate to the charges ##q_1, q_2## (see equations). For example, if ##q_1## is an electron and ##q_2## is a proton, is ##q## just a product or sum or something else of the two? Also, in Columb's law, how would I conceptualize charges ##q_1, q_2## in a system of a...

W=-qEd =-(1.6*10^-19)(23)(0.75) = -2.76*10^-18 J However, the answer is 2.76*10^-18 J. Why is the word done positive and not negative? Since it's traveling in the same direction as the electric field, shouldn't it be negative work?

Electric Motor Start-Up I have done little research into this so far but my "Law of Thermodynamics" alarm is blaring loud-and-clear. Has anyone here heard of this "new motor?" Has anyone tested one in the field?

I was trying to show that the field transformation equations do hold when considering electric and magnetic fields as 4-vectors. To start off, I obtained the temporal and spatial components of ##E^{\alpha}## and ##B^{\alpha}##. The expressions are obtained from the following equations...

These are the 4 distributions shown, and I have to determine which two distributions (or none at all) can use Gauss's law to determine the electric field. So electric flux = EA = Q/electric constant. Since all of them have charges, I could do something like Q/(A*electric constant) to get the...

In an electric field ##E## if the energy of charged particle (ion) is formulated as ##W=qEr## where ##r## is the distance, how the number of particles is estimated?

I tried to find the charge from the formula v=k q/r and apply it to find the field but couldn't be sure

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so the result I got is the energy lost by the field right??

The problem is shown above, the hint to solve the problem is below. See the hint if it is difficult for you to imagine what is going on. I am assuming the diagram in the hint shows what's happening when the mass is falling at terminal velocity. I have quite a few questions. 1. How do the wheels...

I am just a bit confused here. Would doing this even change the electric field direction at the center at all? I'm thinking no, but a bit of direction would be appreciated. This problem is really simple, I'm just a bit confused.

In Robert Wald's General Relativity textbook page 64 reads: __________________________ In prerelativity physics, the electric field ##\vec{E}## and magnetic field ##\vec{B}## each are spatial vectors. In special relativity these fields are combined into a single spacetime tensor field ##F_{ab}##...

Edit: Below is my work but i believe i have chosen the wrong values of the separation vector in the s direction. Any ideas as to what it should be?

Hi all. This is probably a simple question, but I am hoping for some guidance on why a service would be delivered with 4 wires as seen in the image. It appears fairly common around here (northeast U.S.), if not standard, for one of the phase-conductors to be 'double-tapped' and go underground...

Summary:: How to form an automatic billing system through Bluetooth and mobile phones? For commercial purposes, how can my system automatically signal, calculate the billing value and actually perform the billing or transfer the transaction from a credit or debit card or a bank account? [Note...

I tried following the formula but it wasn’t correct. I’m sure I could get it if I had an example as I’m sure this must be a simple question for other people I was just unsure if I was doing it correct.

I know that the answer is 0 J (no NET work was done) because there is symmetry to the problem and this symmetry comes from the fact that the direction of force changes, BUT I don’t know why the force changes (I have an idea; TBD below in #4). When I did this problem I thought I could find the...

Charge QQ is uniformly distributed along a thin, flexible rod of length LL. The rod is then bent into the semicircle shown in the figure (Figure 1).Find an expression for the electric field E⃗ E→ at the center of the semicircle. Hint: A small piece of arc length ΔsΔs spans a small angle...

The last couple of days I’ve been troubled with a specific part of electromagnetism. How will electric field lines be affected by an oscillating charge? More specific, what will happen with the “amplitude” of a wave in an electrical field line as the wave propagate away from the charge? 1. Will...

Dear friends, First of all I have one question! As per Figure 1, how to implement electrical connection in real life which are seen inside Red Box? and what is the meaning of grounding the other terminal? Figure 1 And the second thing is that, I want to create and electric field on copper...

I think the answe should be C as shown in the attachment.

In some textbooks it is given that - Electric charge is the characteristic property of matter that causes it to experience a force when placed in an electromagnetic field. and In other textbooks it is given that - Electric Charge is the property of subatomic particles that causes it to...

I have not studied the Fourier transform (FT) in great detail, but came across a problem in electrodynamics in which I assume it is needed. The problem goes as follows: Evaluate ##\chi (t)## for the model function...

1- Write down the complete MAXWELL equations in differential form and the material equations. 2- An infinitely extensive area is homogeneously filled with a material with a location-dependent permittivity. There are charges in the area. Give the Maxwell equations and material equations of...

So, basically I can follow the math deriving E/B = c from Maxwell. And I can calculate B and H from I: H = I/2*pi*r and B=uH. Easy. So, for example I take a 2000 A, 50 Hz, current and a distance of 2 meter from that current in a round conductor. H and B are set: H = 160 A/m and B = 0,2 mT...

I am not quite sure how to present my answer in the form of a function with relation to the distance from the centre. What I got so far is the E1 and E2, for the internal and external sphere respectively. For internal sphere, the charge is volume * 𝜌, so it is $$ \frac{4\pi r^{3}}{3} * 𝜌$$...

I am trying to calculate the energy within an electric field that is generated between two plates by a pulse but am unsure of what voltage value to use. The pulse is a sinc wave. I am assuming I can still use the equation ## E= \frac{1}{2}CV^2 ##. I know the ##V_{rms}## and ##V_{max}## which...

I need to account for tension, weight, and repulsion. For the tension, I can draw the x and y component of Tmax and see that the x components of the 2 tensions Tmax will cancel out, and there are 2 y components of the Tmax to factor in. Weight is just F = mg, where g is acceleration due to...

Black body radiation formula contains power and exponential terms. Electric discharge in a gas results in the ion acceleration; the ion distribution comprises power and exponential terms too. Any connection between these two phenomena (i.e. black body and potential) could be established?

Hi. I was reading about conductors in electrostatic equilibrium and how it makes sense that they have zero electric field inside the material even when an external charge is brought near. The charge density of the material just rearranges itself to cancel. Then I searched for hollow conductors...

I started from: $$\frac{d}{dt}(m\gamma v_x)=qE\ \ \ \rightarrow \ \ \ m\gamma v_x - p_{0x}=qE(t-0)\ \ \ \rightarrow \ \ \ m\gamma v_x=qEt+p_{0x} $$$$\frac{d}{dt}(m\gamma v_y)=0\ \ \ \rightarrow \ \ \ m\gamma v_y -p_{0y}=0\ \ \ \rightarrow \ \ \ m\gamma v_y = p_{0y}$$$$\frac{d}{dt}(m\gamma...

I think: Due to charge q, there will be a field in region 1, very much dependent on position of q. The inner surface charge density of irregular conductor is also dependent on the position( so that it could cancel the field of charge and E=0 inside body of irregular conductor). The outer...

a) I have calculated (1) λ = ρA = ρπr^2 = 2.49 * 10^-10 C/m and placed it into (2) yielding E = λ / (2πεx^2) = 106.73 N/C. This doesn't seem to be correct by the feedback, however. b) Here just to consider the proportion of the cylinder mass constrained by y.

I know that the electric field is directed from Q to P, but I'm not sure which magnitud is greater, I tried this

Good evening, I'm trying to solve this exercise that apparently seems trivial, but I wouldn't want to make mistakes, just trivial. Proceeding with the first point I wonder if my approach can be correct in describing this situation. From the assumptions, the two fields are in this...

I need to build a battery system to drive a 10 HP pump motor. The actual BHP varies as the pressure in the system rises, but for the most part we are operating at a 10.1 brake horsepower. Run time requirements will vary from a few hours to many hours. I settled on 8 hrs as a basis. Motor...

Here this is my attempt : Reference Textbook : Zangwill's Modern Electrodynamics I stuck at the last step , I really have no idea what to do next.