Induced Definition and 925 Threads

Homework Statement I'm currently reviewing some of the old E&M material that I haven't seen in a while and have gotten stuck on this problem. I'm sure I'm just making a simple mistake but I can't seem to make any headway. Here's the problem: Figure 35-32 shows a copper rod moving with...

Homework Statement THe problem is number 3 in the picture. Homework Equations The Attempt at a Solution Lens law changing magnetic flux through the loop not sure which way for each one little confused. Thank you

Homework Statement Imagine a pliable round metal loop that can expand or contract. In a region with a constant magnetic field B0 that is oriented perpendicular to the plane of the loop, suppose that the loop expands, with its radius growing with time as r = r0(1+at2). As the loop expands and...

Homework Statement A 0.69m long and 0.69m wide loop is moved at a constant velocity of 0.81m/s from a region of zero magentic field into a perpendicular constant magnetic field of 0.21T. Calculate the magnitude of the induced voltage in the loop while it is entering the B-field Homework...

I attached a problem from a practice exam. I'm stuck on part b). Part A, I'm assuming the answer is the standard equation for an infinite current sheet. How do I find induced current? I can only think of using Emf = NBA*ωsintωt Where Emf= I/R, but I don't have resistance. Only other equation I...

Hi, Question: we have a magnetization M_x that varying as M_x(t)=M_x e^{-t}.Threre is a coil on the x axe. The magnetization will induce a current in the coil. How can get value of this current. This situation happen in NMR device. I try to caculate magnetic flux and then voltage (v=-N...

Homework Statement During the design of a new doppler radar unit, you have two circular plates with radius R = 3 cm and a plate separation of d = 5 mm. The magnitude of the electric field between the plates is given as: E = (700 V/(m sec2))*(1-r/Rp)*t 2 where Rp is the radius of the plates...

Homework Statement http://www.xtremepapers.com/CIE/International%20A%20And%20AS%20Level/9702%20-%20Physics/9702_s02_qp_4.pdf <------ CLICK ON THE LINK The Attempt at a Solution Is the above diagram the correct answer ? Please note that the diagram in the question paper is for COIL...

Homework Statement [SIZE="7"]◎ There are two solenoids with their axes parallel, one with a smaller diameter so that it fits inside the other. If the bigger solenoid has a current flowing in the clockwise direction (looked at from above) and the current is increasing in magnitude, find the...

On a finite-dimensional vector space over R or C, is every norm induced by an inner product? I know that this can fail for infinite-dimensional vector spaces. It just struck me that we never made a distinction between normed vector spaces and inner product spaces in my linear algebra course...

Homework Statement I am using these variables: L for the square length - so the rectangle on the left is L/2 by L B' = rate at which field increases λ = Resistance/Length I1 = Current on the right (so the top/right/bottom of square) - goes counterclockwise I2 = Current on the left (so the...

A 30mH solenoid inductor is wound on a form 0.4 m in length and 0.1 m in diameter. A coil is tightly wound around the solenoid at its center. the coil resistance is 5.0 ohms. The mutual inductance of the coil and solenoid is 60μH. At a given instant, the current in the solenoid is 0.3A and is...

Homework Statement A cylindrical solenoid 30 cm long with a radius of 8 mm has 400 tightly-wound turns of wire uniformly distributed along its length (see the figure). Around the middle of the solenoid is a two-turn rectangular loop 3 cm by 2 cm made of resistive wire having a...

Homework Statement A wire loop with area 8.00 cm2 is placed inside a 20.0 cm long solenoid with 5.00×10^4 turns that carries a current of 1.10 A. The loop is concentric with the solenoid. If the length of the solenoid is stretched so that its length increases at a rate of 8.000e-2 m/s, with...

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 half a period. What average back emf is induced in the coil during this...

Homework Statement A parallel-plate capacitor has circular plates with radius 49.0 cm and spacing 2.20 mm. A uniform electric field between the plates is changing at the rate of 1.90 MV/m/s. Find the magnitude of the magnetic field between the plates at a point 12.1 cm from the axis (entirely...

Faraday's Law of Induction: EMF=-\frac{\partial \Phi}{\partial t} If two identical coil with same turns of wire and same dimension ( same cross section area in the middle), one has only air and the other has a magnet core. If the two placed in an uniform varying magnetic field, is there...

(X,\rho) is a pseudometric space Define: x~y if and only if ρ(x,y)=0 (It is shown that x~y is an equivalence relation) Ques: If X^{*} is a set of equivalence classes under this relation, then \rho(x,y) depends only on the equivalence classes of x and y and \rho induces a metric on...

I just need some clarification on the induced EMF Formula.. I know that the negative sign in front of N * dFlux/dt is just an indicator of Lenz's law, but if we were given the magnetic flux as a function of time, would there be situations where -d/dt(F(t)) would be different than just...

Hi, I am doing coursework on Faraday's law of induction. My assignment was to carry out experiments which confirm Faraday's law and also to explain the physics of how faraday's law works... My experiments all worked perfectly, producing straight line graphs showing that: \epsilon\propto N...

A metal wire slides on a horseshoe-shaped metal loop of width 0.25 m. The loop has negligible resistance, but there is a 1Ω resistor in the circuit as well as a 6 volt battery. There is a uniform magnetic field directed into the plane of the page of magnitude 0.5 T. The slide wire is pushed...

Homework Statement A rectangular coil of 90 turns has dimensions of 22 x 65 cm and is located in a uniform 1 T magnetic field. In 1.7 s, the plane of the coil is rotated from a position where it makes an angle of 19° with the magnetic field to a position where it makes an angle of 64°...

Homework Statement A circular conducting loop with radius a and resistance R2 is concentric with a circular conducting loop with radius b much greater than a and resistance R1. A Resistance dependent voltage is applied to the larger loop, having a slow sinusoidal variation in time given by...

I have a question regarding a conducting loop of radius r in a changing magnetic field B. I understand and can determine the direction of the induced current which implies the existing of an electric field that is tangential to the loop. Since this is a closed loop, I am having trouble...

Hi everyone, From what I understand if you had a time varying magnetic field inside a dielectric it will induce a time varying electric field according to Faraday's Law: \nabla\times\mathbf{E}=-\frac{\partial \mathbf{B}}{\partial t} My question is will the dipoles in the dielectric then...

Say I have a solenoid that has a magnetic field Bo Sin(ωt) passing through its axis. What will be the EMF induced in the solenoid as a result ? I know it'll be a function of Cos (ωt) but I am more interested in how my choice of the solenoid will affect the EMF that I'll ultimately measure...

[b]1. The problem statement I'm doing a stimulation. Here is a picture of it. http://desmond.imageshack.us/Himg267/scaled.php?server=267&filename=22904502.jpg&res=medium The questions asks: when moving the voltage slider on the battery and dragging it all the way from right to left, what...

Homework Statement http://tinypic.com/r/rlidg7/5 The picture above shows four different cases of a conducting square loop (in orange), traveling at speed v and passing through a rectangular region. In the left half of the rectangular region, the magnetic field is uniform and directed into...

Hello, I have a problem to understand what people say by "induced metric". In many papers, it is written that for brane models, if we consider the metric on the bulk as g_{\mu\nu} hence the one in the brane is h_{\mu\nu}=g_{\mu\nu}-n_\mu n_{\nu} where n_{\mu} is the normalized spacelike...

Problem: A long vertical wire carries a steady 17 A current. A pair of rails are horizontal and are 0.2 m apart. A 7.6 Ω resistor connects points a and b, at the end of the rails. A bar is in contact with the rails, and is moved by an external force with a constant velocity of 0.5 m/s as shown...

Homework Statement I was just thinking, let's say I connect the north pole of 2 magnets to a ferromagnectic material on both ends, does the whole ferromagnetic material become a north pole? Drawing attached. Homework Equations Nil The Attempt at a Solution I think so.

As it is right now, I'm fairly certain I have E.I.A. I've setup an appointment with my doctor but the soonest I could get one was 2 weeks from now, so I've been trying to further educate myself on it so I could go in with a little bit better of an idea of what I think I have. At first I...

Homework Statement assuming that friction is negligible and tthat electromagnetic forces are constant, (when they occur) calculate the speed of the cart at point 5w this is part IV of a question, so in the other parts and in the given, i found out that: mass of the cart=0.5kg number of...

Dear all, I am gautama currently pursuing my M.Tech in Fast breeder reactor at IGCAR. The project is based on the fuel sub assembly bowing due to thermal, swelling gradients. Using a FEM software ANSYS i have modeled the Sub assembly, but i am not able to give swelling parameter in ANSYS...

The question itself is easy. E field at 2 is zero. E field at other points are of magnitude \frac{\eta}{2\epsilon} But I am arguing with my classmate and tutor that what is the charge induced on the uncharged conductor. For me, I simply use the rule induced charge (charge of same magnitude...

Homework Statement A closely wound rectangular coil of 95.0 turns has dimensions of 29.0 cm by 40.0 cm. The plane of the coil is rotated from a position where it makes an angle of 39.0 degrees with a magnetic field of 1.60 T to a position perpendicular to the field. The rotation takes 0.120 s...

Homework Statement This is seriously going to drive me insane. I know that a time changing B field produces a curling E field. For case #1, I have an open circuited loop with a B field increasing out of the page. This should create a polarity indicated in my picture. I hook up a load...

Homework Statement A very strong magnet is suspended by a non-magnetic thread. A student forms a loop out of a wire attached to the Pasco 750 Interface as shown on the left. During a half second interval, the student moves the wire loop until it is below the magnet as show a) Describe...

Homework Statement A single conducting loop of wire has an area of 8.0×10−2 m^2 and a resistance of 110 Ω. Perpendicular to the plane of the loop is a magnetic field of strength 0.37 T. At what rate (in T/s) must this field change if the induced current in the loop is to be 0.33 A...

So if a circuit goes once around an extremely long solenoid whose changing current causes an induced emf of 360 V (in the circuit) at a particular time, does that mean that regardless of the shape of the circuit, the induced emf will be 1 V per degree? If the circuit has only one resistor whose...

I am trying to make a crude coil gun. I remember that if I run current through a coil of wire, it generates a magnetic field according to the right hand rule. Will the inductance of the coil of wire greatly affect the strength of the magnetic field, or is it mainly due to the strength of the...

Hello, While considering Faraday's Law of Induction, I tried to think of a situation which would expose some difficulties I have with the notion that there is an induced EMF without clear regions of relatively high and low voltage (as in a battery). Here is what I thought would get me started...

Homework Statement A wire carrying a current experiences a force when it is placed in a magnetic field. This phenomenon forms the basis of many devices including the electric motor and the gavlvanometer. The diagram shows a uniform magnetic field B with magnitude 25mT directed towards the...

Homework Statement I'm supposed to draw a FBD with labeled forces of the footpedal and the actual kicking thingy (2 separate system) http://img842.imageshack.us/img842/3812/capture2bf.png Homework Equations No equations really The Attempt at a Solution Well I got all of em right but...

Hi, I have a question about back emf So, my understanding of back emf (\epsilon_b=-L\frac{dI}{dt})is that its the counter voltage that's induced by change in current, whether it be from a battery or magnetic field (\epsilon_0). We can model this as an LR circuit where \epsilon_0 +\epsilon_b=IR...

Homework Statement In a lab I passed a magnet through a coil and measured the voltage. I need/want to know why when moving a magnet through a coil you induce a current. I don't necessarily need a direct answer - I more just want to know if my argument holds and where to look if I'm...

Homework Statement Are these two things not contradicting? Homework Equations The Attempt at a Solution See figure attached. Aren't these contradicting one another? They need a negative sign in there, correct?

How do you determine that direction of the AC current at a given instant in this model. Does it really matter? The red arrows change direction when the coil is horizontal. Does anyone know why the current changes direction at that point? Why does it switch direction at the horizontal and not the...

Homework Statement See figure attached. Homework Equations The Attempt at a Solution If we attempt to solve part a) in this question we encounter several confusions. If we assume i(t) to be a positive current, the magnetic flux will flow through the core in a counter...

Homework Statement See figure attached. Homework Equations The Attempt at a Solution I'm having some confusion about the negative sign within this problem. If you compute the curl of the expression shown in the figure you'll find that it's equal to, -10v_{0} \hat{k} But...