Electromagnetic Definition and 1000 Threads

Homework Statement If the magnetic field of a light wave oscillates parallel to a y axis and is given by ##B_y = B_m\ sin(kz- \omega t)##, (a) in what direction does the wave travel and (b) parallel to which axis does the associated electric field oscillate? Homework Equations The Attempt...

I seem to have a fundamental misunderstanding of the principle here. in the previous part it was required to sketch the graph for the hall probe. I knew since the speed was constant the field was cut at a constant rate hence a straight line was needed. However I did not understand why it...

Quick question about electromagnetic waves traveling through what's basically a capacitor. In the picture I have labelled areas that I'm curious about. 1. Is there a potential induced at A? 2. If yes, is it localized? I suspect the potential would be different at A and B. 3. Is it correct to...

Homework Statement Consider the charging capacitor in problem 7.34 (A fat wire, radius a, carries a constant current I, uniformly distributed over its cross section. A narrow gap of wire, of width w, w<<a, forms a parallel-plate capacitor) a) Find the electric and magnetic fields in the gap, as...

Homework Statement A plane harmonic electromagnetic wave of amplitude Eo and frequency wo is traveling in the positive x direction in a vacuum. It is linearly polarized with its plane of vibration at 45 degrees to the xy plane and the electric field is zero when x=0 and t=0 a) Make a sketch...

Say for you had a wire in a complete circuit inside a magnetic field (pointing inwards) perpendicular to the wire. You move the wire across (to the right) , cutting lines of flux, this induces a current in the wire. The induced current acts upwards using the dynamo rule (thumb is motion...

I've seen derivations for c=E/B and c=1/√μ0ε0, but I don't seem to get the directions right. i.e. I end up with a negative sign in one of the equations. The derivations I've seen do not use vector calculus. One derivation I've seen is in http://Derivation[/PLAIN] of Electromagnetic Waves from...

Wikipedia define EM field as "a physical field produced by electrically charged objects" But there are no electrically charged objects in between cosmic entities and yet Wiki states "The electromagnetic field extends indefinitely throughout space". What am I missing here?

Hi everyone. I'm an electronics eng. student, and, during my studies, and my life outside university, I've heard several times of how electromagnetic fields could affect our body, in a way or another. There are also various resources talking about how these fields can attack cancer...

Homework Statement Hi there. This is not really a problem, I am only trying to understand something but I simply can't. So Rutherford scattering says that $$ \frac{d\sigma }{d\Omega}=(\frac{Ze^2m}{8\pi \varepsilon _0 p^2})^2\frac{1}{\sin ^4(\Theta/2)}|F(q)|^2$$ where $$F(q)=\int \rho (\vec...

For years, I've been tinkering away at an idea for a superhero. Without going into too much detail, I thought it'd be cool if he could tap into, control, and even travel through a number of different types of signals: radio signals, satellite signals, wi-fi, etc. Using brain waves, as well, I...

Homework Statement (See image) a closed circular wire A lies in the plane of the wire B in the circuit. Deduce the direction. Of the induced current in A when (A) the switch is closed (B) the switch is opened (C) the wire A is raised out of the plane of the paper. Homework EquationsThe...

I stumbled upon this article: http://www.comsol.com/blogs/exploiting-symmetry-simplify-magnetic-field-modeling/ Since the article does not contain any mathematical formulations, I was wondering how the boundary conditions can be expressed in terms of magnetic vector potential. From what I...

Hello all I am searching for electromagnetic filters(color filters) for visible region of EM spectrum with narrow bandpass. I want to filter the white beam with continuous spectrom (400 to 800 nm) into red,blue,green and ...with FWHM about 1 nm around each line. Is there such EM filters? How...

Just one last question today if someone can help. I'm trying to derive the electromagnetic field strength tensor and having a little trouble with (i think) the use of identities, please see below: I understand the first part to get -Ei, but it's the second line of the next bit I don't...

Homework Statement I have made an electromagnet using the primary core of a microwave oven transformer and a 1.5 D cell battery. I would like to use the electromagnet to repel an aluminum bar (1 in. dia., 3 in. in length, and 1/4 in. thick; it is shown in the picture) For some reason, the...

How to carry out an experiment to find range of electric force on a van der graff generator?Thanks!

Consider a moving neutron passing by an electromagnet, will a neutron be deflected? This video seem to show that the neutron would have to be charged in order for it to move

I have two wires in parallel at a distance r apart. They are unequal in length. The current carrying primary generates a magnetic field B at distance r. What is the area related to the secondary through which B passes? Is it correct to assume the thickness times the length of the secondary? All...

I understand that when light goes between air and water, refraction occurs (either towards or away from the normal). If the light going between air and water is already going in the same direction as the normal, is there no refraction (or a refraction angle of 0 degrees)? Thank you.

Hi all, Does electromagnetic radiation actually carry kinetic energy? Looking around the web gives different answers. I have seen explanations like radiation pressure experiments as evidence, but this has been argued being effects from energy absorbed by the recipient. In case it does not...

Can anyone give a solution or guidance about how to solve this. In vacuum, the components of an EM wave are Ey = 50(V/m)cos[(5.00 m-1)x + ωt], Ex = 0, and Ez = 0. What is ω?

Hey, guys, I encountered this and confused about it. "In a perfect conductor, an arbitrarily large current can be induced, and the resulting magnetic field exactly cancels the applied field." But I suppose, according to Faraday's law,the magnitude of emf is the rate of change of magnetic flux...

1. The power radiated by the sun is 3.9 x 10^26 W. The Earth orbits the sun in a nearly circular orbit of radius 1.5 x 10^11 m. The Earth's axis of rotation is tilted by 27 degrees relative to the plane of orbit, so sunlight does not strike the equator perpendicularly. What power strikes a...

Hello PPer's, I have been considering the effect to which electromagnetic radiation emitted from stars might play in the gravitational coalescence of galaxies. Surrounding every galaxy there must be a halo of electromagnetic radiation streaming outwards at the speed of light which diminishes...

Electromagentic waves travels at the speed of light that is 3.0 × 10^8. Is the light itself is electromagnetic wave because if the light is a transverse wave which is the electromagnetic wave is transverse too does that makes the light as an electromagnetic wave ?

Matter can neither be created nor destroyed...but potential energy can be converted into a different kind of energy. Let's say we have a spring with a mass connected to it. This mass is a magnet, and the apparatus is inside a copper coil. It's a horizontal magnet with friction minimized at the...

I am confusing about it that what are electromagnetic field books said that it does not require medium then how they propagate in vacuum and we also know that waves are disturbance through a medium

Hello, I was wondering how one would be able to tell the difference between an object emitting a certain wavelength of the EM spectrum, vs. an object reflecting that same wavelength of the EM spectrum. For example: 1) Suppose I have an IR source at 7 microns. I point this source at water, and...

I've attached an image to a conceptual problem I'm having a little trouble understanding. It shows part a, b, c, and d (but d is cut off). a and b are one inertial frame while c and d are another. c and d makes sense, but I'm having a little trouble with a and b. Based on the image for c, there...

As many of you know better than me, photons are the carriers of the electromagnetic force, so they exchange is necessary for example in order to keep an electron around a proton in a hydrogen atom. So how does this work exactly? What is this “exchange”? In the mentioned system, which one of the...

I have to questions that I can't seem to understand. I've seen in my textbook the relation E=cB being deduced from Faradays law applied to some type of rectangular loop. The problem is this is done with regards to a planar wave. So is this relationship general for all EM waves? If so, how? And...

hey, i was wondering if this can be possible by human force, if so why are we not finding this?

Is there different types of light/particles of light? because all of these lights are different how it works, laser light, light from flash light, sun light. Why does flash light only illuminate only less area/more area depending on how much volts the battery is and a sun illuminates a whole...

First of all I'm not sure where in the world this topic would fit at, so I put it in Electrical Engineering because my assumption is that electrical engineers may have the answers for this question more so than anyone else, but mods, if you feel this thread would be better off in a different...

Quick question regarding E-Cals. I am giving a presentation on them soon and I understand just about everything I am supposed to, but I keep encountering one symbol and I simply don't understand what it is supposed to mean. ##\frac{d\sigma}{dx}=\frac{A}{X_0N_A}\bigg[1-\frac{4}{3}x(1-x)\bigg] ##...

So I coiled ~3' of 28awg wire in a 1/4" coil and connected it to an AA battery. It is unable to pick up nuts but still attracts and repulses in the presence of a permanent magnet. When a piece of iron is added to the center of the coil the strength of the magnet increases, as expected, and it is...

hello what are the shapes that a magnetic (of electromagnetic origin, so that it will be able to vary in intensity and switch on/off controlled by electricity) can have? for example, can we create an electromagnetic in the shape of a cylinder of specific dimensions? ie. to produce an...

I know that- The change in current of primary coil changes the magnetic flux linked with the secondary coil and this an emf will be induced in secondary coil (which also has an inductor in the circuit) so current grows in secondary coil and the current in secondary coil produces magnetic field...

hello which is the lightest material that electromagnetism can set it in motion? thanks!

Hey all, I'm new here and hoping to enjoy glorious physics with you all! I have a problem and a question; the problem is I don't know much about electromagnets and want to build something rather involved using an electromagnet. XD The question shall be explained.. General Concept: I'm going...

A convex mirror has a focal length of 16cm. How far behind the mirror does the image of a person 3.0m away appear? I've tried using the equation 1/f = 1/do + 1/di The answer to the solution is -15cm but I'm not sure how to get there. I'm thinking that it might have something that deals with...

How are all of the above fields different from each other what makes them what they are?Any comments would be appreciated.

will the distance traveled by an em wave depends on temperature,if so then explain

I was reading about drift velocity and according to http://amasci.com/miscon/speed.html 100VDC at 1A moving through ~12 AWG wire would produce an electron velocity of 8.4 cm/hr. Since that is incredibly slow I'm curious if a charged fluid (something like the oil used in an oil-based van de...

Homework Statement Hi, I've been unable to find a relevant thread for a question that I've been stuck on for a couple of days now. Here it is; One of the electromagnetic emission lines for a hydrogen atom has wavelength 389nm. Assiming that this is a line from one of the Lyman (nf =1 )...

I don't know if this question should be in the quantum physics section, so I'm just posting it here. So I have doubts regarding matter wave and electromagnetic waves associated with electron or just any particle. 1. So I understand when an electron is accelerated, it produces electromagnetic...

Consider two adjacent people speaking in cell phones. Why the signals don't interfere with one another? Does each phone communicate with a distinct frequency? If so, how?

We originally have $$\overrightarrow{\nabla}\cdot\overrightarrow{B} = 0$$ $$\overrightarrow{\nabla}\times\overrightarrow{E} = -\frac{\partial \overrightarrow B}{\partial t}$$ When electromagnetic duality is concerned this rank 2 tensor kicks in:$$G^{\mu\nu}$$ And most of books and sites...

The magnetic field that is oriented perpendicularly through a 9.2 cm diameter coil of wire drops from 6.4 T to 6.1 T in 0.076 seconds. What is the emf induced in the coil? Trying to answer this. My question is, if they are perpendicular then does that mean that cos90 makes phi = BAcos theta...