In a DC circuit(Yes, keep going), when current starts to flow, and that current needs a bit of time to stabilize to its maximum value. Since there is change in current(increase) there is an increasing magnetic field, a changing flux... that will induce a -V to the circuit. Eventually when...
Homework Statement
A circular coil has N equal loops with diameter C. Each loop has resistivity η and diameter d.
There is a field on the central axis of B(t) = B_0 sin(ωt).
Find the induced current (ignoring other fields)
Homework Equations
emf = -d/dt * flux(t)
i = emf/R
R = η*l/AThe...
Hey everyone I'm new here and this is my first thread, although i have great interest in chemistry and physics my knowledge of these fields is very basic( I'm graduated in economics) so don't be surprised if i ask something that may look silly.
so here are my firsts questions.
-Is it...
Hi all,
I am looking into induced electric fields by changing B fields inside layers of dielectric. For example, if a block of several layers of a dielectric material is placed inside a capacitor plate, the E fields inside each layer is shielded depending on the relative permitivitty...
Hello
here is a problem that we want to find induced voltage in two different questions.
1-here is part (a) solution:
question 1:why we get integral in all space of conducting rail instead of bar space?(Area of bar)for example if we enlarge the space and set bar fix again induced voltage...
This thing has confused me for long .I have not come across any satisfactory answers on my own or while browsing through the internet.
Everybody has seen the example of a rod moving while on parallel rails, with magnetic field perpendicular to the plane of loop formed by rod and rails...
Homework Statement
There's a magnetic field B in +\hat{z}. A rectangular loop is lying in the xy-plane. Three sides are static, the 4th one is moving with velocity v along the direction of +\hat{y}, making the rectangular larger and larger. The length of this moving side of the rectangle is L...
Hi again, I am trying to get a better grasp of induced maps, and trying to see the
results that are used/assumed in defining these maps.
Until recently, I only knew of one type of induced map, described like this:
We have groups G, G' , with respective subgroups N,N' with ##N \triangleleft...
Homework Statement
The right side of a wire loop is dragged to the left across the south pole of a magnet. What will be the direction of the current induced in the loop?
a. No current will flow around loop.
b. Current will move in the wires of the loop in the same direction as the loop...
Homework Statement
In which of the following will a current NOT be induced in the conducting loop?
a. Magnet moving toward upright conducting loop of wire
b. Magnet moving away from an upright conducting loop of wire
c. Magnet moving toward a horizontal conducting loop of wire
d...
Homework Statement
Hey guys, I have a physics II test tomorrow on Electricity and Magnetism, and I cannot seem to figure out this question.
The rectangular loop in the figure has 2.2×10−2Ω resistance.
What is the induced current in the loop at this instant?
Picture:
Homework...
Homework Statement
The problem give is: A solenoid has N=500 windings, radius a=.1 m and a height h = .6m; the current is found to be decreasing according to I(t) = Io - bt, where Io = .4 amps and b = .2 amps/second.
Calculate the rate at which electromagnetic energy is leaving the solenoid...
Homework Statement
In the circuit shown in the figure, the switch S is closed at time t=0 with no initial charge on the capacitor. What is the induced emf if the inductor at time t=0?
Homework Equations
ε=-LdI/dt
The Attempt at a Solution
Initially the inductor acts like a broken...
Homework Statement
A coil with 150 turns, a radius of 5.0 cm, and a resistance of 12 Ω surrounds a solenoid with 300 turns/cm and a radius of 4.3cm; see the figure. The current in the solenoid changes at a constant rate from 0 to 1.8 A in 0.12 s.
Homework Equations
B from solenoid =...
Inside of circular region of radius 10cm shown in Figure 5(a) there is
a uniform magnetic field pointing upwards and three protons held in
place: one at the center, one at a distance of 5cm from the center and
one at a distance 15cm from the center e there is no magnetic field.
The...
Homework Statement
(Challenge Problem 80, Ch33) A rectangular metal loop with 0.050 ohms resistance is placed next to one wire of the RC circuit shown in the below figure. The capacitor is charged to 20 V with the polarity shown, then the switch is closed at t = 0s...
Homework Statement
A rectangular wire loop, 24mm by 36mm, is placed in a magnetic field. The flux density perpendicular to the loop is decreasing in magnitude at a rate of 0.2Wb/m^{2}/s. Calculate the induced emf around the loop.
Homework Equations
The problem is I don't know which...
Homework Statement
A long straight wire carries a steady current. A square conducting loop is in the same plane as the wire. If we push the loop toward the wire, how is the direction of the current induced in the loop related to the direction of the current in the wire?
Homework...
A metal bar with length L, mass m, and resistance R is placed on frictionless metal rails that
are inclined at an angle α above the horizontal. The top end of the rails are connected with a
conducting wire. The resistance of the rails and wire are negligible. The rails are embedded in a
uniform...
Hi everyone, a couple of technical questions :
1) Definition: Anyone know the definition of the induced orientation of a submanifold S of an orientable manifold M?
2)Dividing sets in contact manifolds: We have a contact 3-manifold (M3,ζ ). We
define a surface S embedded in M3 to be a convex...
Hi everybody,
I was wondering how much induced EMF would be produced in a 20cm diameter coil with 100 loops produce. Has anyone conducted such an experiment?
I am interested in quantitative values of the experiment.
Thanks,
KB
Homework Statement
A conducting bar of length L moves with velocity v, in a rectangular region with a uniform and stationary magnetic field B_1. Near the bar, there is a cylindrical region of radius R with another magnetic field B_2 (it may vary on time). Both magentic field are normal to the...
Can anyone explain this excerpt to me? I'm lost on how the positive and negative charges push each other away instead of attract.
Thanks!
P.s
I think this goes in this forum.
Dear All,
I have some doubts in induced charges surface distribution.suppose their is a spherical shell and a negative charge is kept inside the shell(not at the center of shell) then induced charge distribution at inner surface of cavity is not uniform due to eccentric position of charge but...
Homework Statement
A large, thin plastic disk with radius R = 1.1 meter carries a uniformly distributed charge of Q = -7e–5 C. A circular piece of aluminum foil is placed d = 3 mm from the disk, parallel to the disk. The foil has a radius of r = 6 cm and a thickness t = 1 millimeter.
a. Find...
Hi,
We are trying to estimate the likely maximum wave generated from wind blowing along an irrigation canal. We will subsequently estimate runup and the required freeboard to prevent overtopping.
Our canal is ~ 5m deep, has 1:2 side-slopes and a 4.6m wide base. The canal is aligned with...
Hello, I know the magnetic field produced by a direct current flowing through a solenoid has a north and south pole, so how about the magnetic field produced by a current flowing through a straight conductor, does it have a north and south pole too? If it have them, where is it located?
A...
Homework Statement
If we know the orientation of a power line that is parallel to a telephone line, how can we determine the voltage induced on the telephone line without knowing the radius' of the lines? We are told the power line is at 200A at 60-Hz, we know how far each of the lines are...
Homework Statement
A uniform magnetic field B is perpendicular to the plane of a circular wire loop of radius R. The magnitude of the field varies with time according to B=B0exp(-t/τ) where B0 and τ are constants. The time dependence of the induced emf in the loop is
a) exp(-t2/τ2)
b)...
Homework Statement
https://www.writelatex.com/628580dnzrxr#/1303752/
The Attempt at a Solution
As I said in the link above I tried using the surface orthogonal to the cross section of the wire of radius to integrate.
For the line integral I assume it just reduces to E*2(pi)R but for...
Hi,
Homework Statement
I'd like to show that the induced 1-norm satisfies: ∥A∥1=max1≤j≤n∑[i=1 to n] |ai,j|
Homework Equations
The Attempt at a Solution
I realize the sum ∑[i=1 to n] |ai,j| is basically ||Ax|| where x is the j-th basis. I also know that ||A||1=max||x||1=1||Ax||...
I know when the magnetic flux falling on a wire changes, emf is induced and a potential difference is created in the wire, I don't understand how can a change in the flux give electrons potential to create a current what exactly happens when flux changes should I just accept it as a fundamental...
I know when the magnetic flux falling on a wire changes, emf is induced and a potential difference is created in the wire, I don't understand how can a change in the flux give electrons potential to create a current
Homework Statement
A solid conducting disk of radius a rotates about its symmetry axis with
angular speed ω rads/s. If there is a uniform magnetic field \mathbf{B} perpendicular to the disk derive an expression for the potential difference induced between the centre of the disk and its rim...
the title says it all , why does a changing magnetic field* or a moving conductor * induce a current ?
i know the how , i know how it works ,i know that a changing magnetic field creates a changing electric field , but i want to understand how this works on the electronic level , what is the...
The M field is the density of induced or permanent magnetic dipole moments. It is analogous to the P field in electrostatics. In electrostatics, the induced P field in a dielectric is proportional to the applied electric field. This is intuitive to me. Why though, in magnetostatics, is the M...
So, by accident, while deriving the induced metric for a sphere in 3 dimensions I realized that the transpose of the jacobi matrix multiplied by the jacobi matrix (considering it as 3 row/column vectors)will work out the induced metric. Why is it that i≠j ends up being superfluous. One would...
Homework Statement
a coil starts perpendicular to a magnetic field of 0.365 tesla , it has a length of 0.15 cm and a height of 0.25 cm , it rotates with a frequency of 1800 rotation / min . it also has 30 turns
calculate the mean induced Emf during quarter a rotation
Homework Equations...
I am having a bit of trouble understanding something in my textbook and was wondering if you guys could help clarify.
We just learned Faraday's Law that a time variant magnetic field will enduce an emf in a coil. What my textbook says is that " The electric field in the loop is NOT...
Hello, I know that in ideal transformer the law I2/I1 = N1 /N2
I know that I2 is the induced current in the secondary coil, so I1 is the induced current in the primary coil or the current generated from the generator??
where N1 is the number of turns in the primary coil.
and N2 is the number...
Homework Statement
A 104-turn coil rotates 7.14 times per second. The coil has a cross-sectional area of 0.670 m2 and the
magnetic field through the coils is 0.0720 T. What is the maximum emf induced in the coil?
Homework Equations
Honestly the rotating coil is throwing me off. But I...
Hi all,
Let us say I have rubbed cat fur with nylon. Is there any relation for determining the amount of charge (in Coulombs) induced on either of the materials?
Thanks in advance.
> A very long straight wire carries a current I. A plane rectangular coil of high resistance, with sides of length $a$ and $b$, is coplanar with the wire. One of the sides of length $a$ is parallel to the wire and a distance $D$ from it; the opposite side is further from the wire. The coil is...
Consider a magnetic field perpendicular to a conducting ring moving with a velocity, v.When the ring is moving on the ground in translational motion alone, will emf be induced? I am slightly confused because if you consider the two halves of the ring as two rods, emf will be induced in both of...
Homework Statement
Homework Equations
The Attempt at a Solution
Well I tried this (I thought it'd work, but it's not the right answer and I'm not sure how to do it now) Anyway this is my attempt:
\Phi = \mu_{o}\frac{NIA}{\ell} \\ \varepsilon=N\frac{d\Phi}{dt}
So then...
Homework Statement
A wire loop of resistance R and area A has its normal along the direction of a uniform magnetic field, B. The loop is then flipped over in a time Δt so that its normal is opposite to the field. a) Calculate the average induced EMF. b) Find the average induced current. c) If...
A single-turn circular loop of radius R = 0.197 m is coaxial with a long 1740 turn solenoid of radius 0.0410 m and length 0.890 m, as seen in the figure below. (picture in URL)...
If the induced emf = -d(phi)/dt that is the rate at which the flux through a body is increasing, can the induced current ever be more than the actual current so as to oppose the field created?
Because the rate at which the flux through a body is increasing can be greater than the flux it...
Homework Statement
An aluminum ring of radius 5.00 cm and resistance 3.00 × 10–4 Ω is placed on top of a long air-core solenoid with 1 000 turns per meter and radius 3.00 cm. Over the area of the end of the solenoid, assume that the axial component of the field produced by the solenoid is half...
I have come across this problem, who to determine the direction of induced current.
It keeps me wondering why the answer that i got is Fleming's right hand rule?
Aren't it should be Right hand grip rule?
Cz the usual and conventional way of inducing electricity in a solenoid is to pass the...