Induced Definition and 925 Threads

Homework Statement I am having trouble understanding the concept of induced charge separation. In my textbook, there is a diagram that demonstrates the procedure, but it gets confusing because the first image is normal, and then it gets inverted? I don't understand in the second set-up if it...

Confused about voltage induced across inductors :( Hi, As you may have gathered from the topic title, I'm rather confused about inductors :rolleyes: I have another topic going regarding boost converter design, which involves an inductor, but as this confusion/question/observation is really...

ok so you have a current flowing through a wire that induces a magnetic field, the direction of which is given by the right hand rule. my question is: WHY is there an induced magnetic field? what actually causes it? thanks. (fyi I am in classical e&m right now)

Someone who knows what they are talking about: Show what the magnitude of induced emf Homework Statement Consider a magnetic field B = K(x3z2,0, -x2z3)sinωt in the region of interest, where K and ω are positive constants and t is variable time. Show that the magnitude of the induced emf...

Homework Statement An electric field is directed out of the page within a circular region of radius R = 3.00 cm. The field magnitude is E = (0.500 V/ms)(1 - \frac{r}{R})t, where t is in seconds and r is the radial distance (r≤R). What is the magnitude of the induced magnetic field at a...

If a loop is moved in a uniform magnetic field such that the direction of its motion is perpendicular to the magnetic field, then no change of flux occurs. Then according to faraday, no emf is induced... But I was thinking that can the emf be produced in it due to the deflection force?

A magnetic field points into the page. A conductive bar is moved to the right (perpendicular to the magnetic field). Why do the electrons move downwards toward the bottom of the bar? The book doesn't offer a good explanation of this... using right hand rule I would say that the electrons are...

Consider the production of lift only as the reaction force from displacing a mass of air downwards. No matter the mathematical abstraction (Bernoulli, circulation theory) this Newtonian explanation must hold true. So now imagine a rectangular wing in a wind tunnel where the wing spans the...

Homework Statement A light bulb with resistance R is attached on a metal rod which is rotating around the point O on the figure. The metal rod is in contact with an electrical conductor which is a part of a circle with radius d. The metal rod and the circular electrical conductor is a closed...

Basic question on induced emf - ATTACHMENT CORRECTED PLEASE RE-READ Hi Please read the attached doc which is excerpted from the text University Physics by Young & Freedman.The discussion is on the emf induced in a loop made of a superconducting material when a magnet is moved towards it...

Homework Statement Homework Equations I know this is supposed to use Lenz's law, but I don't really understand it V=IR The Attempt at a Solution I calculated the resistance of the circuit to be 6.4e-6 / .0015 = 0.00426666667, but that's as far as i know what to do

Homework Statement In my physics lab, we were asked to connect an unpowered solenoid to an oscilloscope and then move a magnet through the solenoid and observe the changes in voltage on the oscilloscope. First we were asked to move the north pole of the magnet into the solenoid and then the...

I want to model a coil circuit with induced EMF. I want to verify that my model is correct in a circuit. That the voltage developed across the load is calculated correctly. From the equivalent circuit, you can see the current depend on the jX_L and it acts as a low pass filter in the complete...

Hello, Say I have two concentric conducting rings, where r1 >> r2 (why is this important, btw?), and I run a time alternating current I(1) thru the larger one. This will create a magnetic field B (also) thru the smaller ring, which in turn will create itself a magnetic field B2 and so on...

I want to verify the mechanism to which a varying E can induce voltage into a shielded coax. According to Maxwell \nabla \times \vec E = -\frac{\partial \vec B}{\partial t} \;\hbox { and }\; \nabla \cdot \vec E = \frac{\rho_{free}}{\epsilon} From this, with varying E, you induce...

http://planetmath.org/encyclopedia/InducedRepresentation.html The thing I don't get is the definition of a group element g's action on a vector \sigma v. In the link it defines the action as g(\sigma v):=\tau (hv), where \tau is the unique left coset of G/H containing gg_{\sigma}(i.e. such...

Homework Statement A ring falls through a horseshoe magnet. Before reaching the magnet, is the current induced in the ring clockwise or counterclockwise? What about after the ring has passed through the magnet? The answers are clockwise before the ring passes through, and...

[Solved] Estimate induced emf in the coil Homework Statement Consider a single-loop coil whose magnetic flux is given by this image: Estimate the induced emf in the coil at times near t = 0.3s, t = 0.4s and t = 0.5s This is for algebra-based physics. Homework Equations emf = -N*(change in...

I was carrying out a insulation resistance test on a ring main circuit at the dist board in an industrial workshop. The majority of the wiring is single core pvc cables run in metallic trunking and conduit. The majority of circuits have no cpc as the trunking/conduit is being used. When I...

Homework Statement What is the Q value in units of MeV in each of the following processes? i) The spontaneous fission of 232U92 to 145La57 and 87Br35 ii) The neutron induced fission of 232U92 to 146La57 and 87Br35 Explain why heavy nuclei such as 232U92 do not usually undergo fission...

There is one point I am unclear upon in terms of indued charges. If a charge is induced by another charge, will the potential from the induced charge have an effect on the inducing charge. It seems that if it were the case you would be getting (increasing) energy from nothing, however if it...

Hi, All: I am curious to find examples of maps f:X-->X ; X an n-dimensional manifold that induce isomorphisms on , say, the first k<n homology groups, but not so on the remaining n-k groups. I can see if we had maps g:X-->Y, we could start with Y=X, let f be an automorphism...

Hi, I wonder if someone can help me. Looking at magnetic generators, we spin the magnets around which will induce an EMF. This EMF will create a magnetic field opposite that of the magnets, thereby creating a drag. If I had to generate 1 watt for 1 second, how much kg force will I need to...

Homework Statement a). If the resistance of the resistor in Fig. 21-46 is slowly increased, what is the direction of the current induced in the small circular loop inside the larger loop? b). What would it be if the small loop were placed outside the larger one, to the left? Homework...

If you had a lined retangular section solenoid inclined at a angle of 45 deg and you rolled a rod magnet ( just fits inside the retagular section) down it. Would the current induced in the solenoid brake or accelerate the rod magnet.

Homework Statement 90% of the cosmic rays that fall on Earth are protons. So the outside of the Earth is hit by a net positive charge but does not seem to be, in particular, positively charged. How do you explain this? One last thing: I read that a body that is exposed to radiation becomes...

I came across this in my reading and I don't understand: How does the induced eddy current produce a magnetic retarding force FB, and how do we know the direction of FB? Thanks!

I have got a doubt regarding the situation when a ring rolls in a non-uniform magnetic field. We can see that the flux linkage is increasing (considering dB/dt to be positive). So EMF should be induced in the loop. But if we join any two points, say the instantaneous axis of rotation and the...

Hi, What if the inductor coil is wound one way rather than the other. Then the circular flow of current will be clockwise in one case and anticlockwise in the other. And if the inductor is connected to an ac source, then the current will vary. Now in both the orientations, the variation...

How would one go about finding the EMF induced when a two-turn coil of wire is straightened into a one-turn coil?

Homework Statement A coil with 10 windings(radius 0,07m) is inside a homogenous magnetic(B=0,050T) field, it makes an angle of 90 degrees with the field lines so the magnetic flux is at it's max. Over a period of 0,050 seconds it gets turned by 180 degrees, what is the average induced...

I'm doing a lab write-up for physics 2. The experiment is about the title, a bar magnet being dropped through a solenoid. I have to explain four graphs that plot the change in emf (y axis) vs. time (x) axis. There are incoming and outgoing peaks on these graphs. I have to tie these results...

I'm doing a lab write-up for physics 2. The experiment is about the title, a bar magnet being dropped through a solenoid. I have to explain four graphs that plot the change in emf (y axis) vs. time (x) axis. There are incoming and outgoing peaks on these graphs. I have to tie these results...

I am sorry please delete this post if it has been already asked Light is an electromagnetic wave right? i haven't have ever heard of light distorting or causing disturbances in antenna signal,why is it so isn't it also an electromagnetic wave?

Homework Statement A square circuit with side L lies in the x-y plane, is centred on the origin and has sides parallel to the x and y axes. At time t=0 it starts turning about the x axis, in a region characterised by a uniform magnetic field B parallel to z, with uniform angular speed omega...

hi gang, Just building a seismometer I have 2 x 2.5cm disc rare Earth magnets spaced far enough apart for a coil of wire to move between them. Would you expect there to be any difference in induced voltage into a coil between 2 magnets when the magnets are orientated to attract or repel ...

Hi everyone, This question is bothering me for days and would hope to receive some help in this forum. This question is with regards to Faraday's law on EMI. Will an emf be induced when a copper rod is accelerated between a uniform magnetic field? My answer would be no if the rod has...

Electricity affect neurons. For example, in 1791 Galvani made the legs of a dead frog twitch by exposing them to a spark, and more recently in history, electric currents through the brain has been used to deliberately induce "therapeutic" epileptic seizures. What I wonder about is the exact...

Homework Statement Attached below Homework Equations Emf = - \Delta\Phi / \Deltat emf = vBl; motional emf The Attempt at a Solution In the two attached files, there are problems that ask for the direction of the induced current. I understand that the induced current flows in the...

Homework Statement A square wire loop of dimensions L X L (L = 15.5 cm) oriented in the xy-plane and centered on the x-axis enters a region where the magnetic field (B = 0.855 T) is first oriented in the +z- and then in the -z-direction as shown in the diagram below. (Note: W = 15.501 cm and...

Homework Statement A circular metal ring, as shown on the diagram below, is constructed so as to expand or contract freely. In a region with a constant magnetic field Bo oriented perpendicular to it, the ring expands, with its radius growing with time as r=r0(1+\alphat2). As the ring expands...

Hi Forum! I have got a question about the induced scalar potential. I will present the problem from beginning. Lets say we have a Poisson's equation in form: \epsilon \nabla^2 \phi = -4\pi \varrho(r,t) where \epsilon is the dielectric constant. By use of the Fourier transform...

Homework Statement 1. compare the induced voltage of the attached magnet ( two like charges) with the induced voltage of one magnet only? 2.compare the induced voltage of attached magnet (opposite poles) with one with only one magnet Homework Equations The Attempt at a...

Hi everybody It's easy (and well known) to calculate the charge distribution of a condutor in the presence of a point chage. BUT if we change this point charge and put an charge distribution... like a condutor disc, how can I calculate the induced chage of the other conductor?? THANKS

A positive charge Q is located at a distance L above an infinite grounded conducting plane. What is the total charge induced on the plane? (A) 2Q (B) Q (C) 0 (D) -Q (E) -2Q I know the answer is C, but why? Thanks a lot!

Homework Statement "You push a rectangular loop of width .2m, length .8 m, and resistance R=200\Omega into a magnetic field (out of page) Bout=.4 T and a speed v=.2 m/s. The long side of the rectangle is parallel to the x axis. What is the current flowing in the loop?" Homework Equations I...

Homework Statement What is the induced magentic field inside the coil? Attached image shows the coil and direction of rotation. Homework Equations Right hand rule of some sort. The Attempt at a Solution Not sure what hand rule to use to find the induced field in the coil. What...

My classmates had an argument. There are 2 trolleys; one of them (A) is attached to a solenoid wrapped around a soft-iron core, which is connected to a d.c. circuit. There's another trolley (B) which is attached to a solenoid wrapped around a soft-iron core but it is connected to a load...

Homework Statement Find the induced emf in a rotating disc of radius (a) in a magnetic field (B), rotating with uniform angular velocity (w). If the disc is replaced by a rotating conductor of length (a) fixed at one end find the induced emf in the conductor. 2. The attempt at a solution...

I am beginning to read about the topology, I met a problem puzzled me for a while. If Y is a topological space, and X\subset Y, we can make the set X to be a topological space by defining the open set for it as U\cap X, where U is an open set of Y. I would like to show that this indeed...