Induced Definition and 925 Threads

A hypersurface of Euclidean space obtains its Levi-Civita connection by orthogonal projection of ordinary derivatives of vector fields in Euclidean space onto the hypersurface's tangent space. Suppose rather than the unit normal, there is a non-zero transverse vector field and orthogonal...

Homework Statement We have a solenoid with current I and n turns per unit length and (neglecting hysteresis) a ferromagnetic core. Find B and H. Show that when I is varied an electric field is induced and draw it on a diagram. Homework Equations \nabla \times E = - \frac{\partial...

Homework Statement A rectangular conducting loop of dimensions l×w and resistance R rests in the plane of a long straight wire as shown. The closest edge of the loop is a distance a from the wire. The current in the wire is in the upward direction and increases at a constant rate from I to...

Homework Statement A circular coil of area A with N turns rotates at an angular velocity w about an axis perpendicular to its own axis and to a uniform magnetic field B. Find an expression for the induced EMF in the coil in terms of B, N, A, w and time t. What is the orientation of the coil...

At first I thought an induced ion dipole only applied to non-polar molecules, but in the textbook it says it polar molecules are affected by induced ion-dipole forces as well ("for the polar molecule, it enhances the dipole moment already present", Silberberg) ? If that's so, does that mean that...

Homework Statement This is a question from the Princeton Review of AP physics B, 2011 edition. A small circular loop of wire (radius r) is placed on an insulating stand inside a hollow solenoid of radius R. The solenoid has n turns per unit length and carries a counterclockwise current I...

If I have a B field in between two current carrying sheets and I approach this moving at a constant speed. And I have an electron in my hand, when I see the electron move will I say it moved because of an induced E field? Or If I am standing by the plates and I see the electron move into the B...

So I just had an exam and I'm so unsure about this problem. It seems that I got it right, but I could be completely wrong. XD Homework Statement A long, straight current-carrying wire carries an increasing current I that is uniformly distributed over the cross-section of the wire (the...

Homework Statement Parallel plate capacitor with circular plates with radius of 26mm and a plate separation of 6mm. A sinusiodal potential difference is applied across the capacitors plates with Vmax = 170V at a frequency of 60Hz. 170sin(2*pi*60Hz*t) Homework Equations V = ∫E∙dl = El (l...

I know the equation for emf: -dflux/dt= -dB/dt*A . In my case everything is constant accept the magnetic field and I am unable to find the equation for that. I know that is what dB is for but that simply does not work in this case. What is the equation for induced voltage, when everything is...

Homework Statement A circular conducting coil with N=100 turns and radius "r" is oriented in the xy plane. The leads of the coil are connected to a circuit with resistance "R." A time varying external magnetic flux density "B" is applied along the z-axis. What is the total magnetic flux...

Say I have a closed metal rectangular shaped wire in a region with a magnetic field. If the magnetic flux is constant, there is no induced current, no experienced force, and no EMF? If I start the changing the magnetic flux, I suppose by increasing the magnetic field, there will be an...

Homework Statement Uniform time varying magnetic field \vec B_{(t)} pointing at z direction, filling up a circular region on xy-plane. Find the induced E field. I tried two different ways and get two different answers. Please tell me what did I do wrong. Homework Equations Emf...

1. The problem. A circular loop of radius 4cm has a plane which is perpendicular to the electric field B. (The area vector is +k, so is the field vector.) The strength of the field varies with time according to the equation B=4/(t^3). Give an expression for the voltage as a function of time...

Homework Statement In a cylindrical region of radius R, there exists a time varying magnetic field B such that dB/dt=k(>0) . A charged particle having charge q is placed at the point P at a distance d (> R) from its centre O. Now, the particle is moved in the direction perpendicular to OP (see...

Hi there, If a proton passes through a loop of wire, it induces a tiny current in the wire. Will the proton lose energy and slow down as a result of this? If so, by how much?

I am taking a few medications that have *nightmares* listed as the main side effects. I am having a lot of nightmares. What could cause this? How could the medication change normal dreams into nightmares? Wouldn't nightmares be different for each person? I now have dreams that range...

Homework Statement The square loop in the figure below is made of wires with a total series resistance of 10.0. It is placed in a uniform 0.100 T magnetic field directed perpendicular into the plane of the paper. The loop, which is hinged at each corner, is pulled as shown until the...

Homework Statement Hey guys, This is just a qualitative question. So assume I have a massive super large magnetic field, and pull a straight, isolated conducting wire sideways through it with constant velocity. I know that the EMF induced is given by emf = Blv where l is the length of the...

Homework Statement This is not really a question, just a concept I am trying to understand. I understand changing magnetic field induces an electric field - but how does it do this? Homework Equations The Attempt at a Solution I figure since the changing magnetic field would...

Apologies if this is not in the proper location/format/etc; first post. In a very short (3 min) segment on MythBusters, they unsuccessfully tried to induce a current in a loop in the same plane as a current carrying wire (AC). I originally assumed this didn't work because the B field was not...

Please note, I'm not in school anymore -- just a basic physics question! Homework Statement A conductor is placed inside the coil of an induction heater. Imagine that the inductor coil has radius R, number of turns N, operating frequency f [Hz], drawing current I = I0 * sin(2*pi*f*t). The...

Homework Statement I have a few homework questions that ask for the direction of induced current for ex a loop of wire. I can't figure out how to find it .

1. In the figure the square loop of wire has sides of length 2 cm. A magnetic field points out of the page; its magnitude is given by B = 4.0 t^2y where B is in teslas, t is in seconds and y is in meters. Determine the emf around the square at t = 1.50 s...

what is the difference between eddy current and induced current? and how could eddy current cause energy loss? does the induced current cause also energy loss? what is the difference between back emf and induced emf? all these things are confusing me. thanks in advance

According to the faraday's law,the induced emf is proportional to the magnetic flux change linking the conductor.However,I wonder why there is induced emf when conductor is moving in uniform magnetic field,because i think that the magnetic flux linking to it is always the same as it move in...

Homework Statement Two metallic rings A and B, identical in shape and size but of different resistivities Pa and Pb are kept of the top of two identical vertical solenoids. When current I is switched on in both the solenoids in an identical manner, the rings A and B jump to heights ha and hb...

Homework Statement A flat coil of area A and n turns is placed at the centre of a ring of radius r(r2>>A) and resistance R. The two are coplanar. When current in the coil increases from 0 to i, the total charge circulating in the ring is? The Attempt at a Solution dQ=dΦ/R Initial...

Homework Statement I just took a test, and I am very unsure of the validity of how I approached the problem. Just looking for some feedback cause this is bugging me! There is a circuit in the xz-plane (vertical), and the circuit has on it a gate. The gate is a pendulum of length L, which...

Hi all, I recently came across one of the proposed mechanisms by which black hole could be formed as stated above.Can someone please explain me what is it all about? Also what's their relationship with type IA supernovae? I always thought that, a black hole is formed only when a main sequence...

Faraday's law says that an induced voltage across a conductor is directly proportional to the rate of change of magnetic flux through the conductor, but I am having trouble getting my head round how it works in this situation. Imagine a perfectly circular thin copper disc, and that this disc...

Hi there, When you have a loop of wire and you move a bar magnet through it, you induce a current in the wire. What if you were in a room where there was a magnetic field (not moving) that was stronger than the magnetic field produced by the magnet? If you moved the magnet through the loop...

I have a question about calculating induced surface charge: Consider a system composed of an infinite grounded conducting sheet located at z=0 and a point charge positioned some distance d above the sheet. Via method of images, we can find the potential in the region z>0. When we are done, we...

There's no electric field inside a conductor, a classic observation of electrostatics. Any field that "should" exist is compensated for by charge redistribution on the surface of the conductor. This produces classic results like shielding since in a hollow conductive shell, the field is still...

Homework Statement A square loop of side .45 m is placed in a region where there is a magnetic field of strength 8T directed perpendicularly out of the plane of the loop. If the magnetic field is increased to 14 T in .03 seconds, calculate the average emf induced in the loop Homework...

Homework Statement Hey everyone, I'm studying for a final and have been having difficulty determining induced magnetic field and current direction. I have a document (link below) with 5 sample problems. I answered them all, and put my reasoning for the answers there in italics. Would...

Hi there, If you have a stream of protons passing through the inside of a coil of wire (coils of wire at 45 degrees to current of protons) and say the current of protons induced a certain current in one of the loops, would the current induced in one loop be equal to the current in the entire...

Suppose now i have connected a solenoid with a dc power supply of 10V When i increase the voltage to 20V the magnetic flux through the coil have increased will emf be induced shortly to oppose the change? what if i now change it to a 10V ac power supply so will there always be induced emf...

Homework Statement 2 parallel long, straight conductors lie on a smooth plane surface. 2 other parallel conductors rest on them at right angles so as to form a square of side 'a' initially. A uniform magnetic field B exists at right angles to the plane containing the conductors. Now they start...

Hi, everyone: Given a top space X, and a homeo. h: X--->X , we get an induced map (by functoriality ) h_*: Pi_1(X)---> Pi_1(X) . We can also write the map as a map g: Aut(X) --->Hom(Pi_1(X),Pi_1(X)) Is the map g always surjective.? . Almost definitely...

In a 1964 publication Bruno Rossi describes an experiment where cosmic rays could penetrate dense materials. Finding that cosmic radiation at sea level could penetrate over 1m of lead. In these same experiments he was also surprised to record a higher rate of detection, as many as 35 per hour as...

Homework Statement Determine the emf induced in the square loop in the figure if the loop stays at rest and the current in the straight wire is given by I(t) = (15.0 A)sin(2500t) where t is in seconds. The distance a is 12.0 cm, and b is 15.0 cm. Homework Equations In the question...

If a time varying magnetic field of infinite dimensions crosses a plane at right angles what can we expect induced electric field lines to look like? Straight lines with direction determined by the right hand rule?

Hey guys, I have a scenario where I can't figure out what would happen. If I have a magnetic sphere traveling down a track made of two conducting wires (each with current flowing through them)... what would happen? I'm not sure how the magnetic field of the wire and the magnetic field of...

Homework Statement A square coil (25 x 25 cm) that consists of 50 turns of wire rotates about a vertical axis at 1000 revolutions per minute. The horizontal component of the Earth's magnetic field at the location of the coils is 2 x 10-5. Calculate the maximum voltage induced in the coil by...

Homework Statement [PLAIN]http://img220.imageshack.us/img220/2589/44045733.png Semicircular wire MN of diameter L moves with speed v perpendicularly through a uniform magnetic field of strength B. 1. Find the magnitude of the induced emf generated between M and N. 2. State whether M...

Hi all Physics (masters) I was reading a paper on the faraday's induction experiments; i didn't quite understood the reason why is current induced into a solenoid. There is this solonoid and a Permanant magent is pushed inside the solonoid and we observe that a current flows (by a...

Sometimes when i swipe my card at walmart it doesn't read it , And the guy was like let's put it a plastic bag and then try it, and it works and I've heard a couple of other people doing this. So when i slide my card the magnetic strip induces a voltage and reads the card. So why does...

Homework Statement A flat coil of wire consisting of 20 turns, each with an area of 50 cm2, is positioned perpendicularly to a uniform magnetic field that increases its magnitude at a constant rate from 2.0 T to 6.0 T in 2.0 s. If the coil has a total resistance of 0.40 Ω , what is the...

Hello everyone, i have a question about induced voltage that i need help answering, in my calculations i believe i have made a mistake about the total voltage induced in the coil. My calculations follow as: 390 RPM / 60 Seconds = 6.5 Hz x 6 pole pairs = 39 Hz x 6.28 = 244.92 radians per second...