Induced Definition and 925 Threads

I read many different explanation but none of them is satisfying. There is two cases: 1. I move an iron rod in a magnetic field, between two bar magnet for example. To this case I read that when I move the rod the electrons on it also move and moving charges produce magnetic field which...

Homework Statement The coil in a loudspeaker has an inductance of L = 56uH (or 5.6 x 10^-5 H). To produce a sound frequency of 20 kHz, the current must oscillate between peak values of +2.2 A and -2.2 A in one half of a period. What average back emf is induced in the coil during this variation...

The induced matrix norm for a square matrix ##A## is defined as: ##\lVert A \rVert= sup\frac{\lVert Ax \rVert}{\lVert x \rVert}## where ##\lVert x \rVert## is a vector norm. sup = supremum My question is: is the numerator ##\lVert Ax \rVert## a vector norm?

Homework Statement A loop of wire and a bar magnet are moving relative to one another. Which motion in the diagrams shown below will NOT induce a current in the loop? Homework Equations Lenz's Law: A changing magnetic field can induce a current in a direction that produces its own...

Homework Statement Q If an object having charge 'q' is brought near an uncharged conductor (sphere) , would the charge induced on the nearby surface ( closer to the charged object ) be equal to '-q' ? Homework EquationsThe Attempt at a Solution I think the charge induced would be less than...

Homework Statement If there is an uncharged metal spherical body and a charge q outside it .Find Electric field due to induced charges. Homework Equations ##E##=##\frac{Kq}{r^2}## The Attempt at a Solution If there is an uncharged metal spherical body and a charge q outside it then there will...

Homework Statement A 21cm×21cm square loop has a resistance of 0.12 Ω . A magnetic field perpendicular to the loop is B=4t−2t^2, where B is in tesla and t is in seconds. (A) What is the current in the loop at t=0.0s? (B) What is the current in the loop at t=1.0s? Homework Equations for a...

Homework Statement Question I need help with: If wire AB of problem 9 moves with a velocity of 50.0 m/s to the right, at what rate should B change when the wire is at a distance of 5.00 cm from the left end of the loop, such that there will be no induced emf in the circuit? Answer: 300 T/s...

Time-varying magnetic field makes electric field circular(or close loop). I am asking the reason why it is circular or close loop shape?

Homework Statement hey! I saw you've answered this question before... Hi, I would appreciate any help with the following: The coil in a loudspeaker has an inductance of L = 112 microH. To produce a sound of frequency 40kHz, the current must oscillate between peak values of + and - 4.4 A in...

Homework Statement Show the the induced charge density on a dielectric placed inside a capacitor is given by $$\frac{k-1}{k}\sigma$$ where ##\sigma## is the charge density of the capacitor plates and ##k## is the dielectric constant. Homework Equations $$E=\frac{E_0}{k}$$ The Attempt at a...

From this diagram: If a conductor of length(##L##) is moving with a velocity(##v##) inside constant magnetic field(##B##), there is an induced EMF as indicated at the top of copper slab, and connected to a load and current will flow. I've been curious with the way the wires are connected to...

I have a problem. So the curl of the E field is supposed to be zero always, which tells us that it is a conservative force (path independence and scalar potential and so on). But what about the fact that the induced electric field consequent upon changes in magnetic flux is circular? Doesn't...

If you have a one solenoid inside another (with the same number of coils of wire) the current is going through the inner one. How does the induced EMF in the outer one depend on the frequency of AC in the inner one

Hi, I found a statement without a proof. It seems simple enough, but I am having trouble proving it because I am not positive about induced matrix norms. The statement is that $$||A^k|| \leq||A||^{k}$$ for some matrix A and positive integer k. I have found that the norm of a matrix is the...

Hi, I'm trying to use LIBS technique to figure out elemental analysis of human nails. But every time i run the experiment, i get the emission line of metal instead. The sample holder is indeed made up of metal. What should I do to overcome this problem? Since i have small size sample, I'm...

Homework Statement Charge Q is uniformly distributed on the rim of a thin insulating disc of mass m, radius R, which is initially at rest and placed on a smooth horizontal surface. What will be the angular velocity of the disk if a magnetic field B, perpendicular to the plane of the disk, is...

I am having trouble with deducing the origin of Maxwell's Laws, especially Faraday's Law. Obviously some of the laws has to be originated by experiments and the rest should be mere deductions. I would guess that Lorentz force law is the empirical information where we just named some terms as...

Hi, I was wondering whether anyone can help with a question I have about the forces acting on a car wheel and the forces the wheel induces on the ground surface. The way I understand it, a car wheel traveling on a flat surface has the following forces acting on it: -vertical force due to the...

Induced charge can never be greater than inducing charge ,but can it be equal to inducing charge?I think yes.But in my book it is given that "In induction the charge induced in the near surface of a dielectric is lesser and dissimilar, lesser implies not equal.Why? I think it is something to do...

I read the following problem on a textbook: A airplane flies at a constant speed of 680m/s perpendiculary to Earth's magnetic field (of 5x10^-5 T). The wingspan of the airplane is 9.8m. What is the induced voltage? The answer the book gives is: E = BLv = 0.4066V But I've been wondering if this...

Let's say I place two different size conducting loops inside of a uniform magnetic field. For the sake of the diagram I have the loops share a point, but just treat them as though they are not touching. Then I decrease the value of the magnetic field very quickly. \frac{dB}{dt} =...

Homework Statement Two long rods with distance between them a=100mm, over those two rods there's another rod sliding, friction between them is negligible. The rods are placed in homogenous magnetic field whose B is equal 1T, with direction shown in the picture, between the rods there is voltage...

Homework Statement Faraday's disk with radius of axle r1 and radius of disc r2 is shown in the picture below. Disc rotates in the homogenous magnetic field whose vector B is vertical to the disc. If disc is spinning 1000 rpm find induced voltage between r1 and r2 and what is maximal value of...

Consider a loop which is subjected to a magnetic flux variation. Among the points that turn there will be the electromotive force induced?

Im a bit confused about one point. Can Eddy current, and induced current exist at the same time...? If a conductor is a part of a closed circuit, and there is a change in magnetic flux over time, both Eddy current and induced current would oppose that change? Let's assume a conductor that is a...

The book I am working through is beginning to dive into induced currents and Lenz's Law. When a conductor is moving perpendicular to a magnetic field, the charge carriers inside will experience a magnetic force; This causes the charges to move. Eventually, the electric field from the charge...

Assume we have the following copper slab, with volume ##V##, and introduced a magnetic field covering a small area of it like so: There is change in magnetic flux(##\phi##) due to the magnetic field increasing/decreasing, and via Faraday & Len'z law of electromagnetism, there is an induced...

Homework Statement A coil of insulated wire is wound many times around an iron bar. The wire is connected to a battery and a contact switch. The contact switch is alternately flipped closed and left closed, so the wire carries a current through it, and then flipped open and left open, so that...

If we have a conducting loop, and a magnet (say North pole first) is pushed into it; that induces and emf and hence a current in the coil due to the changing magnetic flux, right? According to Lenz' law, the direction of the current is such that it opposes the change. So from the side the magnet...

Hello, Microwaves are classified as non-ionizing radiation, so my question is, how do microwaves separate atoms into positive ions and electrons? I've heard of multi-photon ionization, is this what happens?

Homework Statement [/B] A conducting square frame of side a and a long straight wire carrying current I and located in the same plane as shown in the figure. The frame moves to the right with a constant velocity v. The emf induced in the frame will be proportional to Homework Equations [/B]...

Hey all! I have a question about induced voltage and magnetic force "acting together". What I mean is that I know that when there is a perpendicular magnetic field acting on a wire that has current going through it, it will produce a magnetic force perpendicular to both magnetic field and...

I see a lot of problems on constant current inducing a current in another wire due to its associated magnetic field, but not so much a single wire's induced electric field. If the current along an infinitely long wire is flowing out of the page and inducing a counter-clockwise spinning magnetic...

Imagine there is a hollow toroidal conducting chamber and a long solenoid in the middle. When we power the coil, does the induced electric field "propagate" inside the chamber? My prediction is that the changing flux will cause induction regardless of the cage. Thank you.

When we move a wire through a magnetic field appears a magnetic force that distributes loads at one end of the wire ( following equation F = q⋅(vxB) ), until an opposite force is generated on the wire by the electric field (E) caused by charge distribution. This causes the EMF or induced...

Homework Statement If ##A## is the subspace of ##l^\infty## consisting of all sequences of zeros and ones, what is the induced metric on ##A##? Homework EquationsThe Attempt at a Solution The metric imposed on ##l^\infty## is ##d(x,y) = \underset{i \in \mathbb{N}}{\sup} |x_i - y_i|##. I...

Homework Statement There's a primary and secondary coil. The primary coil has 15 turns, and the secondary coil has 16000 loops. The 25000 V is applied to the primary coil, what will be the induced emf in the secondary coil. Homework EquationsThe Attempt at a Solution Very confused as to how...

Homework Statement Let g_{\mu\nu} be a static metric, \partial_t g_{\mu\nu}=0 where t is coordinate time. Show that the metric induced on a spacelike hypersurface t=\textrm{const} is given by \gamma_{ij} = g_{ij} - \frac{g_{ti} g_{tj}}{g_{tt}} . Homework Equations Let y^i be the coordinates...

Homework Statement A solenoid has 500 turns per meter and cross-sectional area 4cm2 Current through it is increasing at 100A/s and flows in a clockwise direction. There is a wire loop, concentric with the solenoid which sits outside the solenoid. Given that the magnetic field inside the...

Homework Statement Use Lenz’s law to answer the following questions con- cerning the direction of induced currents. Express your answers in terms of the letter labels a and b in each part of Figure P31.22. (a) What is the direction of the induced current in the resistor R in Figure P31.22a when...

Hey people I was wondering why is an emf induced in a loop which moves perpendicular to a uniform magnetic field. I mean, say the loop is a square of area r^2, and moves in the xy plane, where there is a uniform magnetic field B in the z direction. Why will an emf be induced? The flux remains...

1. Homework Statement Based on what I've got, i guess the answer is A. However, I'm not quite sure of myself. From what I can see coil Y has its own magnetic field because current is flowing in that coil. When there's a flow of current there will be a magnetic field around it. Thus, placing...

can we still induced e.m.f in a circuit if we switch on and off the circuit. Well, since induced e.m.f is proportional to the rate of change of magnetic flux. I guess alternating the switches can changes the magnetic flux of a circuit. Please correct me if I'm wrong ^_^ .

Hi everyone, I am currently stuck on this problem, and I was wondering if I could get assistance, at least in getting started. It'd be greatly appreciated!

when A current-carrying conductor is placed in A magnetic field due to the interference of both magnetic fields,the field is made variable so a force will be induced on the Conductor. so my question is, If an Ac current is passed through conductor it will have variable magnetic field will it...

Hi friends..I'm struggling with an interesting puzzle...Suppose there is a circular conducting loop of radius 1/π cm, one half of which is made of a material with resistance 1Ω and the other half from a material with resistance 5Ω. If somehow, one managed to set up a changing magnetic field...

Homework Statement Homework Equations ∫BdL = μI The Attempt at a Solution a) the magnetic field is a circle around the wire so the length of the path is the circumference of the circle which is 2πr ∫BdL = BL = μI B(2πr) = μI B = μI/2πr in this problem it is into the page (right hand rule)...

Currently doing my A2 Levels and have just been revising over electromagnetic induction. The general consensus seems to be that current can only be induced in a changing magnetic flux.The textbook I'm using constantly refers to cutting a magnetic field, i.e. moving a wire relative to a field, to...

Problem statement, equations, and work done: A perfectly conducting cube is placed in a uniform electric field in the x direction (see attached). Step1 : Use Gauss's law to determine the electric field inside the cube.##\phi_E = 2E(r)A = \frac{q}{\epsilon_0} →...