All Questions
Tagged with electromagnetic-induction magnetic-fields
514
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How to calculate retarded potential (for magnetic field calculation) for a group of current carrying loops where the magnitude of current is changing?
For constant current, the magnetic field seems to be easy to calculate because of Biot-Savart Law. For a loop having varying magnitude of current (simplifying an electromagnet), however, it seems that ...
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0
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What is the induced electric field in a moving conducting material in a magnetic field?
I've been taught that the induced EMF in a conductor is the rate of change of flux in it, but Maxwell's equation
$$
\nabla\times\vec{E} = -\dfrac{\partial\vec{B}}{\partial t},
$$
only states so for ...
- 1,613
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Flux and emf induced graphs when magnet is dropped through a coil
I've been told that if you drop a magnet through a coil the induced emf and flux graphs would look like this:
I understand that when the bar magnet is in the middle of the coil the emf induced is ...
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Does making a magnet move require more energy than a non-magnet?
I know that electric fields store energy, with their energy in an infinetesimal volume being proportional to $E^2$ at that point. I also know that a moving magnet creates an electric field (...
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Electric field of moving charge
Does the electric field of a moving charge (constant velocity) change with time? Or it remains the same?
I know that changing electric fields produce a magnetic field, but in a straight, current-...
CommunityBot
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3
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1
answer
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Explaining how a magnetic field affects currents in a conductor, in the limit of high conductance
Recently, I gave an answer to this question,
explaining my intuition on how much electric field impinges into
a good conductor under certain conditions, in order to reason about the limit of
perfect ...
CommunityBot
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0
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Self-induction in a permanent magnet
when a permanent magnet is moved in a coil, an emf is induced in the coil. so is an emf also induced in the magnet itself? and if not then why not. and if I replace this permanent magnet with a ...
- 207k
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648
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Finding induced magnetic field strength given current.
I'm working on a project involving a Tesla Coil, and I was hoping to figure out how strong an induced magnetic field would be with an input voltage of X. Is there an equation to help solve this? I'm ...
CommunityBot
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6
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Why does a changing magnetic field produce a current?
A changing magnetic field induces a current in a conductor. For example, if we move a bar magnet near a conductor loop, a current gets induced in it.
Faraday's law states that
The E.M.F. $\...
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What logic is being used in Bleaney & Bleaney to prove the reciprocity theorem for mutual inductance?
I'm currently reading Bleaney & Bleaney 3rd Ed. On pg 136 they discuss the case of 2 coils. Their logic is as follows:
If a second coil is brought near to a coil carrying a current $I_1$, there ...
- 126
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9
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Induced current density and magnetic field arising from forced oscillations of particles in a constant magnetic field?
I am being confused by what should be a simple physical scenario. Let's say I have a small, cylindrical region of radius and height are both $a$ filled with a medium of both positive and negative ...
- 207k
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3
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Faraday's law and motional EMF
My understanding of motional EMF is that one of the ways it is created is by moving a conductor (moving such that its orientation doesn't change) in a uniform magnetic field (non changing). EMF is ...
CommunityBot
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4
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729
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How do Electric and magnetic fields generate each other (mathematically)?
Regarding electromagnetism, a changing magnetic flux$(\phi_B)$ produces emf by-$$EMF= -\frac{d \phi_B}{dt}\tag1$$
This emf creates a current which again creates a magnetic field given by-(bio-savart ...
- 13.1k
2
votes
2
answers
705
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What factors does magnetic field due to a circular loop depend on?
I know of three.
Strength of current
number of loops ( a cheeky way to 'increase' current?)
radius
I'm having doubts about radius of circular loop affecting the magnitude of magnetic field ta ...
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1
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Induced Electric field due to magnetic field in Faraday experiment
Regarding this experiment where a magnet is moved in and out of a coil -(see the picture)
what i considered to be true is that when there is a changing magnetic flux through the coil(due to changing ...
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