Questions tagged [electromagnetic-induction]
This tag is for questions regarding to electromagnetic induction, a process in which a conductor is put in a particular position and magnetic field keeps varying or magnetic field is stationary and a conductor is moving. Electromagnetic Induction was first discovered way back in the 1830’s by Michael Faraday.
1,899 questions
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Induced voltage in a ring: what is the contour path for Faraday's Law?
I’m quite puzzled when it comes to reconciling the induced voltage in a circular conducting loop with Faraday’s law. Suppose I have a ring with an outer/inner diameter of 5 m / 4 m. This ring is cut ...
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How is electromagnetic induction related to the motor effect? [duplicate]
I am learning physics at a pretty basic level (GCSE) and two concepts I need to know are: the motor effect, where a current-carrying wire feels a force when moved through a magnetic field as long as ...
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Induced emf vs induced potential difference meaning for conductor moving entirely within magnetic field
My students were recently answering an AP physics 2 question that asked them whether an emf would be induced in a circular loop of wire as it entered a magnetic field and then later when it was moving ...
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Extremely High Inductance
In the Harvard natural sciences demonstration page, they write that they have built an LR circuit demonstrating a visible time constant by using a 20000 turn 45 kH inductor in a circuit that has 4.7 k$...
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The classic induction bar on a rail - Has anyone does this?
There is an extremely common set up for analyzing electromagnetic induction and the currents and forces thus involved: The sliding conductive bar.
I think every person who studies physics is ...
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What would the circuit diagram of the magnetic equivalent circuit of this specific ferromagnetic actuator look like?
This first image shows an illustration of the actuator I am attempting to create an equivalent circuit for. .
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this second image shows it modelled in FEMM.
In the third image I have attached, this ...
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Why is it impossible to have a localized surface current at the boundary for an Ohmic material with finite conductivity?
My question is regarding a statement from Orlando, Delin: Foundations of applied superconductivity.
We are trying to solve for the fields inside an Ohmic conductor. A slab is considered parallel to ...
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Accounts for changing Kinetic energy of electrons in a circuit
I will take a purely inductive circuit to explain my query. In a purely inductive circuit, the current keeps increasing lineraly with respect to time forever. As current is also lineraly related to ...
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Magnetic energy discrepancy
Suppose we have a coil with constant magnetic field through its core $\overrightarrow{B}_{ext}$. Now we connect the coil to a battery such that it produces magnetic field in the opposite direction to ...
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Current induced in a wire when coil wire is longer than the magnet and the magnet is in middle of the coil
Here is the original question :Current induced in a wire when coil wire is longer than magnet
I have made these two figures to explain the point OP is trying to make :
Magnet falling through the coil ]...
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Is it possible to measure scalar potential difference with a voltmeter/oscilloscope?
In what follows I will deal with quasi-statics, where the fields can vary in time, but they are slow enough that there are neither retardation nor radiation effects. For brevity, I will also happily ...
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Determining the polarity of motional EMF on an airplane flying West to East in the Northern Hemisphere
I am trying to determine the charge separation on the wings of an airplane due to the motional electromotive force (Hall Effect) in the Earth's magnetic field.
An airplane is flying from West to East ...
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Will rotating a charged circle in a radial magnetic field produce linear momentum? [closed]
Imagine the following experiment:
Assume that the red rod is a hypothetical north magnetic monopole while the blue torus is charged with a positive charge $q$. The blue torus is rotated as shown.
Q
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Measuring mechanical power of a PMDC electromotor
So I have this problem. I want to measure the efficiency of an experimental PMDC motor. As you know 𝜂 = P_out / P_in, in the case of a PMDC: 𝜂 = P_mech / P_el. P_el = VI, but P_mech is a problem. I ...
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The integral form of Faraday’s law seems nonlocal, what's wrong?
Consider this example I met in my physics class:
An infinitely long cylindrical region contains a uniform magnetic field
$B$ within it whose magnitude varies with time. Determine the induced electric ...
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