Induced Definition and 977 Threads

Homework Statement Homework EquationsThe Attempt at a SolutionThe emf gets induced due to the changing flux. The flux through the rod remains 0. So, there is no induced emf. I don’t know how to calculate induced electric field. But as there is no induced emf, so there is no induced...

Hello How do I calculate the induced voltage in a passive signal cable that runs parallel to a 1 phase power cable? Cable A is the power cable I = 500 A Cable B passive signal cable where: D= 209.65 mm: distance between wires ( center wire to center wire) r= 10 mm: radios of each wire f=60...

In my experiment, I intended to find out how the change in the bar magnet drop height from solenoid affected the emf induced in the solenoid, however, I am unable to come up with an equation that shows a relationship between the two variables. I have thought of Biot-Savart law, but I do not...

Homework Statement A square loop, side a, resistance R, lies a distance s from an infinite straight wire that carries current I (pointing to the right). Now someone cuts the wire, so I drops to zero. In what direction does the induced current in the square loop flow, and what total charge...

How would you calculate the induced magnetic field B at some distance R from a bar magnet, given the magnetic moment of a magnet? (In general)

Homework Statement I have a circular loop with a radius of 1 m. The center of the loop is located 2 m away from a infinitely long current carrying wire, with ac current I. Find the flux in the circular loop Homework Equations Φ = ∫ B ds The Attempt at a Solution I've found a lot of examples...

Homework Statement This is irodov's problem #310 in electrodynamics A long solenoid of cross-sectional radius a has a thin insulated wire ring tightly put on its winding; one half of the ring has the resistance ## \beta ## times that of the other half. The magnetic induction produced by the...

Let ##p: X-->Y## be a cover map. Then the induced homomorphism will inject the fundamental group of X into the fundamental group of Y; furthermore, the image of the fundamental group of X under p will be a subgroup of the fundamental group of Y I read the proofs, but I'd like to have an...

Homework Statement Homework EquationsThe Attempt at a Solution First part is easy . Area of the triangular loop is A = (1/2)(2R)(R) = R2 Induced EMF in loop ABC = Rate of change of flux = dΦ/dt = AdB/dt = R2(dB/dt) which is correct . Now the second part has stumped me . I would really...

Homework Statement The circuit in Fig. 32-31 consists of switch S, a 12.0 V ideal battery, a 20.0 M resistor, and an air-filled capacitor. The capacitor has parallel circular plates of radius 5.00 cm, separated by 3.00mm. At time t=0, switch S is closed to begin charging the capacitor. The...

I'm doing a little experiment on reducing iron oxide back to bare iron. I'm going to use a blued rod, coconut oil and ultraviolet light. Im using coconut oil because information from this site suggests that it is very transparent to uv light. https://www.hindawi.com/journals/jspec/2013/540417/...

All sites and books give different answers for this question:( Homework Statement predict the polarity of the capacitor in the diagram below Homework Equations right hand thumb rule AB is capacitor The Attempt at a Solution The side facing south pole becomes south and north facing side...

Homework Statement In Fig. 32-4( a) there is a uniform magnetic field in the + x-direction, with a value of B = 0.20 T. The circular loop of wire is in the yz-plane. The loop has an area of 5.0 cm2 and rotates about line CD as axis. Point-A rotates toward positive x-values from the position...

Homework Statement A current of 10A is switched off at time t = 0 in a long cable (picture in attachments). It powers a device, with the current return wire having 5 mm separation. A wire loop of dimension 5 by 5 cm is located at a distance 3 cm from the cable. 1) What Emf is induced in the...

If there is a rotating wire in a constant magnetic field what is the direction of the induced current ? The problem is the direction of the area vector which is arbitrary, if it is parallel to the magnetic field the current will flow in a direction, if it is anti-parallel it will flow in the...

I am struggling with the concept of induced current in a circuit consisting of an inductor and how that induced current establishes back EMF . Please see the page of the textbook attached . There is a circuit consisting of an inductor , a series resistance (not shown) and a battery ( not shown...

I'm an undergrad biochemistry major at a state university in NY (I've tried the chemistry forums already) trying to understand more about interactions between polar and non-polar molecules. Say I have a thin wax in water, we are taught that the entropy of the reordering of water contributes...

Homework Statement Homework Equations N/A The Attempt at a Solution [/B] I'm having a lot of trouble understanding induced magnetic fields. I was wondering if someone can explain it for me and confirm if I have the right answers? a) I labelled it [North | South], and the direction of the...

Homework Statement (ignore the suggested problems for test 3.) If for whatever reason the image doesn't load the given's are that: The area is 25pi(.125m)^2 (A circular coil with 25 turns and a radius of 12.5cm.) The magnetic field varies with time and is...

HI! I'm a student, this question appeared in one of the old tests. I though I had it solved but apparently I must have missed somewhere. Could someone please at least hint me where I went wrong? Homework Statement Thin wire is wound into circular frame with radius ## r = 0.05m ## which...

In a transformer, the primary coil has a current running through it which creates a magnetic field. Then this field induces a current in the secondary coil. That induced current creates a magnetic field exactly opposite the inducing magnetic field. This might be an obvious question, but that...

Hello! How can ordinary material become radioactive, if exposed to radioactive sources? I read that Marie Curie's notes are still radioactive and I am not sure I understand how. As far as I know gamma and X-rays can excite or ionize an atom or excite a nucleus. How does this make the radiated...

Hi, I was wondering whether a bar magnet would induce a current if it was moving external to the solenoid, rather than within the coil. I see no reason why it wouldn't occur, but I've never seen it displayed or mentioned so I'm not sure. Thank you.

If I have some arbitrary conductor moving through a (nonuniform) magnetic field \mathbf{B}(\mathbf{r}), would the induced field in the frame of the conductor be something like: \mathbf{B}_{IND}(\mathbf{r}) = T \mathbf{B}(\mathbf{r}) where T is some diagonal matrix whose entries are related to...

Homework Statement An aircraft has a mass of 1100kg and a wingspan of b=9.75m. the surface of the wing is 15m2 and its span effciency factor e=0.90. the parasitic drag at zero lift of the aircraft CD0 is 0.0225. Take density of the air to be 1.225kg/m3 The aircraft has lost power and is...

Homework Statement An aircraft has a mass of 1100kg and a wingspan of b=9.75m. the surface of the wing is 15m2 and its span effciency factor e=0.90. the parasitic drag at zero lift of the aircraft CD0 is 0.0225. Take density of the air to be 1.225kg/m3 The aircraft has lost power and is...

Homework Statement A thin and straight metallic rod of length L is rotating about its middle point with angular velocity ##\omega## in a uniform magnetic field B. The axis of rotation is perpendicular to the length of the rod and parallel to the magnetic field. The strength of the induced...

In class we were trying to calculate the induced electric field created by changing the magnetic field stregth. Imagine there's a circular surface which magnetic field out of the screen.Since we are changing the magnetic field from Faraday's Law there should be a induced current or charge flow...

Hi, Let's think 2 arbitrary shape conductors with non zero charged. If these 2 conductors are closed, there will be induced charge density over surfaces of these conductors. I have not seen such an example, instead there are lots of problems which involve zero(grounded) potential case and...

Homework Statement The figure shows a metal coil labored as A. Heading torwards a region where a uniform static magnet field exists, poiting torwards the ground (hence X). The coil moves with the same constant velocity. As it enter the magnet field the coil will have an induced current in it...

Homework Statement A 5.0-cm-diameter coil has 20 turns and a resistance of 0.50Ω. A magnetic field perpendicular to the coil is B=0.020t+0.010t^2, where B is in tesla and t is in seconds. Find an expression for the induced current I(t) as a function of time. Homework EquationsThe Attempt at a...

Hello all - I've stumbled upon what seems to be a pretty basic magnetic materials question that's got me stumped. Maybe one of you can help me figure this out. I did the following experiment (see figure below): Put a ferrite toroid around a current carrying wire carrying 12 Amps RMS at 120V...

Homework Statement Homework Equations induced emf = - d(magnetic flux)/dt The Attempt at a Solution [/B] I believe the graph will start initially curving upwards, because it begins to cut more and more flux lines which lead to an increased induced emf. Once it is "fully" within the...

Hello there, Suppose ## \Delta = r^2 + 2GMr + a^2## and ## \rho^2 = r^2 + a^2 \cos ^2 \theta ##. The Kerr metric is $$ ds^2 = - (1 - \frac{2GMr}{\rho^2})dt^2 - \frac{4GMar\sin^2 \theta}{\rho^2} d t d \phi + \frac{\rho^2}{\Delta} dr^2 + \rho^2 d \theta^2 + \frac{\sin^2 \theta}{\rho^2} \left[...

i made a speaker from a cup, a coil of wire and a magnet. I hooked up both of the ends of the wire to a headphone jack and it works. Albeit very low sound, but it works. Can you point me in the direction of some equations that will show me the most influential factors on how to make it louder...

Hello everyone, I am working on a 3.2 meter wing span electric aircraft with another group of 30 engineering students. In calculating the induced drag and lift for preliminary calcs I am a little confused as to whether I need to include the width of the fuselage in the wing span(b) for induced...

it is something like this but instead of the rectalve contour iswith the angle 37 degree!https://www.physicsforums.com/attachments/114624 1. Homework Statement the speed of the slide is 0.16 m/s the length of the slide is 0.14 m the angle of the contour is 37 degree Homework Equations...

Homework Statement A small coil of wire is situated in a non-uniform magnetic field. The coil consists of 40 turns of wire and moves with a constant speed in a straight line. The coil has displacement x from a fixed point P. The variation with x of the magnetic flux in the coil is shown in the...

Homework Statement A generator consists of 500 turns each of surface area 7/11 m² . It rotates at rate of 50 revolutions per second (f =50 Hz), in a field of magnetic flux density of 5*10^-4 T, its terminals were connected in series with a capacitor (Xc=110Ω), an inductor (Xl=80Ω) and a...

Homework Statement Calculate the surface charge density induced by a point source above an infinite conducting plane, with 0 potential. Homework Equations ##E=-\nabla V## ##V=\frac{q}{4\pi \epsilon_0 r}## The Attempt at a Solution I used the method of image charges and I calculated the...

Hello! I am a bit confused about calculating the induced surface charge density on an infinite conducting plane, with 0 potential, in the presence of a charge, q, a distance d above it. Assuming that the plane is in xy plane and the charge in positive z region, in the book they use the method of...

I have been trying to search for answers on the Internet, but to no avail. For induced magnetism, i understand that a magnetic material can turn into an induced magnet under the influence of a magnetic field. However, i do not understand how to magnetic poles are determined. Suppose a perm...

Homework Statement 2 movable conducting bars on a conducting rail with a uniform magnetic field heading inside the paper , what will happen to bar 2 if we move bar 1 to the left with a velocity v ? 3. The Attempt at a Solution i think that a current will be induced in bar 2 and pass to bar...

Homework Statement A metal ring with a radius of 10cm and resistance 0.1Ω passes through a delimited magnetic field, look at the photo posted below. The ring has a velocity of 5m/s, and the magnetic field has the field strength 0.4T. When the ring passes through the magnetic field, at some...

Homework Statement Two large parallel metal plates are oriented horizontally and separated by a distance 3d. A grounded conducting wire joins them, and initially each plate carries no charge. Now a third identical plate carrying charge Q is inserted between the two plates, parallel to them and...

In Purcell- Electricty and Magnetism book, in the chapter on electromagnetic induction, I found the following explanation regarding the magnetic flux through a circuit of area ##S##. Consider the circuit in figure, moving in a time ##dt## in a magnetic field ##B##, constant in time (but not...

The integral form of Maxwell's equation pertaining to induced electric fields is: ∮E(t0)⋅dℓ= −dΦ(t)/dt|t=t0Say for a long time, in some circular region there has been no B or E fields present. Then, there is a sudden constant increase of B field introduced in the middle. I know that information...

I would really appreciate some clarification about how to draw graphs showing changing flux and induced EMF. I understand that there needs to be a 90 degree phase difference as the EMF is a maximum when the flux has the greatest rate of change. However, our exam board says that the EMF can be...

The induced emf in a straight wire is determined by the equation (emf=Blv sinθ) where θ is the angle between the direction of the motion and the lines of the magnetic field, and frequently, I see diagrams like these explaining the phenomenon: In those pictures the wire is perpendicular to the...

Homework Statement Explain what happens in the following situation: You have a loop in the form of a circle and there is a varying magnetic field inside that loop as the following picture illustrates: Homework Equations Faraday's law lorentez force The Attempt at a Solution I first thought...