Induced Definition and 977 Threads

Homework Statement Homework Equations - The Attempt at a Solution The relative velocity of magnet with respect to ring is 5−4=1m/s How can I find the Direction of induced current in conducting ring due to motion of bar magnet? I searched online and found this ...

Homework Statement A charge is located a distance 'a' above a sheet of metal. The charge density induced on the sheet of metal is (-2aQ)/(4pi(ρ^2+a^2)^(3/2)). Since there are no dimensions indicated for this plate, would it be plausible to assume that we are integrating from zero to...

Hi, Assume that one has a pair of metal spheres, A and B, some distance apart. A is connected to, say, a small van der Graaf generator and B is connected to a voltmeter which is then connected to ground. I expect charge to be induced on sphere B. How would one calculate the voltage one...

As part of a Griffiths problem, I have a charged capacitor placed in a uniform magnetic field which points in +x direction. the capacitor plates are parallel to xy planes. Suddenly, the B field starts decreasing in magnitude...what is the direction of the induced E field? It makes most sense...

Homework Statement The problem I would like to ask is in Griffiths Introduction to Electrodynamics p358 problem 8.6 part (c)Homework Equations The Attempt at a Solution The answer is $${\varepsilon _0}EBAd\hat y$$ which is same as part (a) Here's how I found a loophole:One key information that...

Hello, Does anyone know what "induced gravity" is and where can one read (something not too technical) about it? I am trying to understand how a system with zero Lagrangian has something to do with gravity. Could someone explain perhaps? Thanks

Homework Statement http://grephysics.net/ans/9277/54 I am confused about this. The explanation for why the induced current is clockwise is because the induced current would resist the change in magnetic flux, therefore work to increase the magnetic field. But if the current induced in the...

I wasn't sure where to post this question, so I posted it here. As the title suggests, I want to know how to calculate (at least roughly) the electric field induced by excitation and ionization of a material (such as a metal) using a high intensity laser. My final goal is to compare the...

Homework Statement I don't understand why the answer in this problem is choice A. http://grephysics.net/ans/9277/57 I'm confused. Lets say the semi circle is FULLY outside of the circle. For awhile after that, the semi circle would be accelerating the rate at which a certain % of it is...

i am just being curious about some details about how laser can induce charges inside a glass bulk? Does anyone else have more knowledge on this?

In the classic problem of the induced EMF in a moving conductor (as in the picture above), the calculation for the induced EMF is as follows E=\frac{d\Phi_B}{dt}=\frac{d(BA)}{dt}=\frac{Bd(A)}{dt}=\frac{Bd(Lx)}{dt}=\frac{BLdx}{dt}=BLv. The derivation assumes that the magnetic field B is...

When a positive point charge q is brought close to a neutral conducting spherical shell then negative charges will be induced on the part of the shell closer to q and equal positive charges will appear on side of the shell farther from q.I understand this part. But if the conducting spherical...

Why will there not be an induced current in a field parallel to a current carrying wire?

This is discussed in Weinberg's Quantum Theory of Fields, in the chapter on Relativistic Quantum Mechanics. The point I am somewhat confused about occurs on page 63 - 64, if you have the book. He operates on a single particle state with the unitary homogeneous lorentz transformation...

please elaborate their difference in your own word.. thanks! (SURVEY)

If an arbitrary shaped conductor is moving through a steady-state magnetic field, \mathbf{B}(\mathbf{r}), is it true that the field induced in the conductor will be proportional to \mathbf{B}? IE: \mathbf{B}_{induced}(\mathbf{r}) = M \mathbf{B}(\mathbf{r}) where M is a 3-by-3 constant...

If a wire moves with some constant velocity (4 m/s for example in the diagram) parallel to the direction of the wire itself (unlike in most physics problems in which you drag a wire 'sideways' or perpendicular to the direction of the wire) but still perpendicular to the magnetic field, what is...

These are 2 straight wires parallel for 3 inches. Specifically a 6AWG and 12AWG separated approximately 2 inches. A surge current enters on the 6AWG which has a rising edge of 2500A/us. This is for a surge device ... I have been working in plain old RF for too long to be certain that I using...

Homework Statement A hollow spherical conducting shell is suspended in air by an insulating string, so that the sphere is electrically isolated. The total charge on the conductor is -6 μC. If an additional point charge of +2μC is placed in the hollow region inside the shell, what is the total...

Assuming there is a time varying magnetic field (B) , how to determine the direction of the induced electric field due to B. and to which parameters does it depend?

Can anyone tell me the site or give information on these i have small doubts in that so can anyone give exact answer When a sinusoidal input is applied to circular coil of N turns what is the magnetic field generated around it and what is the induced voltage in an other circular coil of...

A magnetic field of B=0.5B0z^ is present when a loop with radius r is rotated around the y-axis with angular velocity of w=9 rad/s. What is the induced emf? Well: flux = SB*dA = SBdAcosq(t) = Bcosq(t)SdA = 0.5B0*pi*r^2cosq(t) d(flux)/dt = 0.5B0*pi*r^2*-sinq(t)*dq(t)/dt =...

Two identical uniform beams are connected together by a set of servo motors. When the motors activate the two beams will come together uniformly and the center of mass of the system will move outward along the arrow shown. I would expect that the torque exerted by the motors would only cause the...

Homework Statement A point charge q is placed at a distance ##r## from the centre O of a uncharged spherical shell of inner radius ##R## and outer radius ##2R##. The distance ##r<R##. Find the electric potential at the centre of shell.Homework Equations The Attempt at a Solution The charges...

Hi all, Perhaps I'm asking the wrong question but I am wondering about the relationship between different definitions of, for the sake of argument, the torus. We can define it parametrically (or as a single constraint) and from there work out the induced metric as with any surface. But...

Homework Statement An aeroplane in horizontal flight has a wing span of 50 m and is traveling due north at a speed of 500 kmph. Calculate the emf induced between the wing tips of the aeroplane. The value of the vertical component of the Earth’s magnetic field is 5.5 x 10-5 T. What...

Homework Statement A small, 1.60-mm-diameter circular loop with R = 1.40×10−2Ω is at the center of a large 120-mm-diameter circular loop. Both loops lie in the same plane. The current in the outer loop changes from 1 A to -1 A in 8.00×10−2 s. What is the induced current in the inner...

How to determine the direction of emf induced in an alternator without the need to look at the graph. (i.e) using Lenz's Law or Faraday's Laws of determining the direction? Consider for example the instant when B and dA are perpendicular and no flux is present? Thanks for helping!

Homework Statement See attachment. Homework Equations The Attempt at a Solution For the first part: (B' and x' are B subscript 0 and x subscript 0 respectively.) \phi=BA=B'xl=B'l(L+x'cos(ωt)) EMF=-d\phi/dt=-B'ωlx'sin(ωt) Therefore V=-EMF=B'ωlx'sin(ωt) So...

Homework Statement A point charge Q is placed at a perpendicular distance a from an infinite planar LIH (linear, isotropic, homogeneous) dielectric of relative permittivity ε. By considering the normal component of the electric field at an arbitrary point just inside the dielectric to be the...

Can any ine tell from where i can get this information If a single turn circular coil generates a magnetic field around it how can we calculate the induced voltage in a single turn circular coil located at a distance of d

Dear colleagues, My question here refers to the EMF induced in an incomplete ring that is stationary amidst a time dependent magnetic field. We know from Faraday's law that EMF is created upon changing the magnetic flux, either by changing the intensity of the field, or by changing the...

Homework Statement so there's two solenoids on the same axis of symmetry, and the smaller one inside the larger one has a resistance of 11 ohms, 1000 turns, and radius .02 meters. the outer solenoid has n 18000 turns per meter, and had a current that is increasing at a constant rate with...

Homework Statement A small, 1.60-mm-diameter circular loop with R = 1.10×10−2Ω is at the center of a large 120-mm-diameter circular loop. Both loops lie in the same plane. The current in the outer loop changes from + 1A to -1A in 8.00×10^−2s . What is the induced current in the inner loop...

Homework Statement I'm working on induced currents/b-fields from Lenz's Laws and two different problems use the same equation but one has an extra variable and I don't know when to add this equation. Problem 1: In a physics laboratory experiment, a coil with 180 turns enclosing an area of...

Homework Statement I'm working on induced currents/b-fields from Lenz's Laws and two different problems use the same equation but one has an extra variable and I don't know when to add this equation. Problem 1: In a physics laboratory experiment, a coil with 180 turns enclosing an area of...

A charge Q is kept at a distance x from one of the plates of a parallel capacitor having plates d distance apart with cross section area A.The whole system is earthed.Find the value of induced charges on both the plates. I tried putting the sum of induced charges equal to Q and balancing...

Homework Statement The magnetic field strength at the South Pole is around 66μT, and magnetic field lines point out of the Earth perpendicular to the surface. The sled is a metal square of side 0.95 m (with non-conducting wooden slats in between). What is the magnetic flux through the sled...

Homework Statement Estimate the fundamental frequency of resonance sound induced by blowing on the open end of a half liter bottle Homework Equations f= 1c/4L The Attempt at a Solution i don't know the length of L, what's half liter bottle ..? What does it tell you? 2 x f1?

Homework Statement I have attached the two questions. the first has a diagram. 1. Find the MAX Induced EMF (in volts) in the loop by the changing current? 2. What is the magnitude of the EMF induced in the loop by the changing current at t=.8 (seconds) answer in Volts? Homework...

When you use Faraday's law to calculate the induced electric field due to a changing magnetic flux, you integrate over a loop defined by the circuit you're interested in. Why is the electric field confined to the circuit? Couldn't I just pick a random loop in space and integrate over that...

Homework Statement Homework Equations The Attempt at a Solution Their answer assumes that the B-field is perpendicular to the velocity at all times, which is clearly not the case. And in the next part of the question, won't the answer be zero? since now velocity is parallel to B-field? (So...

Homework Statement http://img805.imageshack.us/img805/6030/82154948.png Find Vemf (between points 1 and 2) and it's polarity at t = 0. I have omitted details because my question is specifically on the polarity.Homework Equations Lenz's law: An induced electromotive force (emf) always gives...

Because according to Faraday's law there should be a change in the flux to generate electric potential for a current to take place. But in that case no flux change happens. This can be reasonably explained by Lorentz force(charge separation due to radial Lorentz force) but can we still apply...

Homework Statement Sorry for the blurry picture. If the coil is being pulled away from the loop shown to the right, in what direction is the current induced in the loop? Homework Equations right-hand rulesThe Attempt at a Solution I assumed it to be clockwise just from looking at the...

Homework Statement It is often discussed that a changing magnetic field will create a non-conservative electric field, which would then induces an EMF and hence an induced current, but what happens when we connect voltmeters? Consider putting a circular loop of wire with some resistance in...

Homework Statement Let R be an arbitrary ring, B and B' be left R-modules, and i: B' \to B be an R-module morphism. Show that if the induced map i^*: \operatorname{Hom}_R(B,M) \to \operatorname{Hom}(B',M) is surjective for every R-module M, then i: B' \to B is injective. The...

A flat, rectangular coil of dimensions L and w is pulled with uniform speed v through a uniform magnetic field B with the plane of its area perpendicular to the field (the figure (Figure 1) ).How is the emf zero? My reasons as to why it's zero: the trig part forces the problem to be zero...

Hi I'm a first year undergrad student studying Electronics. I am really interested in creating a working Laser Induced Breakdown Spectroscopy(LIBS) setup in my summer break which is June and July. I'm reading about it these days, although still scratching the surface. I'm confused whether I'll...

Homework Statement A coil of wire with N turns is placed around the a long solenoid with n turns per unit length carrying a current I as shown below, A)If a current I flows through the solenoid, derive an expression for the magnetic flux through the coil and explain why the size and shape...