Questions tagged [induction]

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351 questions
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Why can't mutual inductance create perpetual electricity?

Consider the following image. When the battery is connected then current starts flowing through the primary cicuit and magnetic flux changes through the coil, this causes electricity to be induced in ...
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What does direction of EMF mean?

In faraday's law it mention's direction of EMF( like in closed loopit is clockwise or anticlockwise depending on direction of motion of magnet) but defination of EMF is roughly Potential diffrence ...
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Can induction coils heat air?

I understand that induction coils can heat up conductive materials such as metals, but I'm wondering if they can heat up normal air. And if they cannot, can ionizing the air beforehand allow it to be ...
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how is motional EMF developed?

According to my textbook and several other sources on the internet if we we move a rod in the direction perpendicular to a uniform magnetic field, the electrons will also move as per the direction ...
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How to calculate induced emf of moving rod?

I have the following exercise: A copper rod with length L is moving on two frictionless conducting rails, in a distance a from an very long straight conductor. The rods resistance: R. Ignore any self ...
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Does displacement current occur in an inductor?

We have learned in school that displacement current comes about due to a change in electric field flux per time in a capacitor (Ampere-Maxwell Law). Does the same displacement current come about in an ...
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What would happen if a magnet was pushed towards a copper tube in space?

So the question was inspired by one of curious comments on youtube. What exactly would happen if you pushed a strong neodymium magnet towards the copper tube (aiming for the opening in an effort to ...
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currents in an isolated metal exposed to an alternating uniform electric field

For example, let's look at a metal sphere between a capacitor's (infinite) plates. Let's run an AC current through the capacitor, resulting in an oscillating electric field. The charges will move in ...
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Is it possible to use Ampere's law to calculate vector B around short straight line conductor?

Maybe this question sounds easy, but I would really be grateful if someone could give me an explanation if it's true or not. I'm not sure if I understand it good enough.
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Why induction coupled plasma use RF frequencies?

The frequency I see all the time is 13.56mhz,I understand that when you want to make heat treatment surface finish on steel,you use high frequency in the heating coil so the skin effect heats only the ...
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Why will a magnetic field cause a ring to hover?

I was attempting a homework question which went like this: Where the crosses indicate a magnetic field in that rectangular region pointed into the screen, and we're asked which of the rings would ...
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Violation of conservation of energy (seemingly) in process of electromagnetic induction

A bit long question but it's really bugging me a lot. Say we have a closed circular conducting loop at rest and initially a bar magnet rests along its axis with north side facing the loop. Now we ...
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Only getting positive values for induced voltage? [closed]

We have to draw a voltage over time graph for the induced voltage in a coil for 2 whole turns. $N = 10$ $B = 30mT$ $A = 100cm^2$ The coil is rotating at 20Hz We have the formula: $2πNBAfsin(2πfT)$ ...
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How eddy currents effect the impedance of source?

When we connect a bigger resistance to a transformer, the current decreases both in the primary and secondary. To be able to maintain the same current, we'd have to increase the voltage. Now imagine ...
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Finding the voltage across an inductor when opening the switch [closed]

Well, I've the following circuit: In the circuit I want to find the voltage $\text{V}_{\text{Y}_1}\left(t\right)$ as a function of time, after I open the switch (this switch was closed 'forever' ...
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Measurement of electrostatic induction

How is it with the electrostatic induction measurement? Everywhere you can read about the effect of electrostatic induction but I still can't found any detailed explanations or quantitative ...
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Point charge inside a electrically neutral cavity in conductor placed eccentrically, and effect of external electric field if switched on

bear with me, but i would like a definite answer, now, starting off the external charge density on the outer surface of sphere WILL be uniform by unique solution of Laplace equation and letting the ...
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What is the QM equivalent of induction?

And regarding electron correlations, reciprocally what QM ones are strictly due to classical induction and near field effects? Edit: thanks to whoever thinks necessary to downvote questions without ...
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Transformer and magnetic field/flux through the iron core?

I am familiar with how a transformer works. This is the diagram that I found on the wikipedia page: The current through the red solenoid varies with time, which creates a time-dependent magnetic ...
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Ed Leedskalnin's “Perpetual Motion Holder” (PMH)

Edward Leedskalnin (Coral Castle) describes a perpetual motion holder in his writings. I've built one and pretty much know how it works (I think). It is NOT a perpetual motion device by any means, ...
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Now what will happen in this circuit?

Consider a circuit as shown in this figure below- Assuming switch S1 is closed such that current flows in loop ABCDE for a long time and steady state is reached. Now, my question is simple, suppose (...
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Why is the integration constant in a purely inductive AC circuit assumed to be zero?

While studying about AC circuits, I came across the usual differential equation of an AC circuit (in which the voltage across the source is a sinusoidal function of time) containing an inductor only. ...
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How do Eddy currents follow conservation of energy?

When wind blows, leaves of a tree move and they gain kinetic energy. In this case air molecules loose kinetic energy and transfer it to the leaf. But In case of eddy currents moving inside a conductor,...
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This was my grandfather’s and have no idea what it is only that it is some piece of physics equipment! The main black cylinder doesn’t seem like it wants to rotate but not sure if it should?
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How to calculate the limits for volume and mass for induction heating samples?

I'm evaluating the feasibility of using volumetric induction heating to quickly heat up steel molds. One thing I have come across is that induction heating really only works for surface heating or for ...
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Is there is any way to prove the Faraday's law of induction?

I want to know if there is any way to prove the Faraday's law or is it just an experimental observed phenomena? More specifically, is there any reason why the proportionality constant is 1? How did ...
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Is Faraday's induction principle applicable in outer space?

Is it possible for an AC generator to actually generate electricity let's say being in a ship orbiting Mars or on the surface of the moon? Does Faraday's principle require the magnetig field of the ...