46 votes
Accepted

What happens to an inductor if the stored energy does not find a path to discharge?

Suppose an inductor is connected to a source and then the source is disconnected. The inductor will have energy stored in the form of magnetic field. But there is no way/path to discharge this ...
Thomas Fritsch's user avatar
35 votes

What happens to an inductor if the stored energy does not find a path to discharge?

It depends. You cannot disconnect an ideal inductor from an ideal voltage source with an ideal switch. These ideal things will break your calculations and you will get an infinite voltage on ...
fraxinus's user avatar
  • 7,906
31 votes

Does a Mobius resistor have zero inductance? How would you calculate the inductance?

The inductance can be calculated, but it is first necessary to look at the behavior at very fast timescales of a ns or so. Clearly the two faces of the strip form a transmission line and so, at short ...
Truth's user avatar
  • 589
20 votes
Accepted

Where does the extra energy come from in an LC circuit?

The energy is not used up. It goes to the magnetic field, and when the magnetic field is at its strongest value there is no energy left in the electric field of the capacitor. But then the magnetic ...
octonion's user avatar
  • 8,700
16 votes
Accepted

Where does the energy stored in inductor go on opening the switch?

This is a situation where the simple rules are insufficient. You simply cannot analyze that circuit any more than you can solve x+2=x+3. What happens in the real world is that the inductor creates ...
Cort Ammon's user avatar
  • 49.1k
12 votes

Where does the extra energy come from in an LC circuit?

It depends as to whether you are considering the LC(R) circuit in isolation or with a alternating voltage supply as the driver. The series of diagrams illustrate what might happen if the capacitor ...
Farcher's user avatar
  • 96.2k
12 votes

An *actual*, relativistic, intuitive explanation for inductance…?

To echo Dale’s comment, the idea that the magnetic field doesn’t exist is an extremely common misconception for some reason. What relativity tells us is that electric fields and magnetic fields mix ...
J. Murray's user avatar
  • 69.2k
11 votes

What happens to an inductor if the stored energy does not find a path to discharge?

But there is no way/path to discharge this energy? What will happen to the stored energy, current and voltage of the inductor in this case? In that case it makes its own circuit with its own path to ...
Dale's user avatar
  • 100k
10 votes
Accepted

Lagrangian method for an $LC$-Circuit

In this answer, I'm going to use $Q$ instead of $q$ for the capacitor charge. There is only one certain rule for finding Lagrangians: The Lagrangian is chosen such as to get the correct equations of ...
DanielSank's user avatar
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10 votes

Is Back EMF produced in household wires?

In theory you are right. The wires indeed produce a counter-EMF. But let's get some concrete numbers. The inductive reactance of a wire is $$X_L = 2\pi f L \tag{1}$$ where $f$ is the frequency of the ...
Thomas Fritsch's user avatar
9 votes
Accepted

Inductor and Capacitor in Parallel

My book says the current through the inductor would pick up to 0.2A, while the current through the capacitor drops to 0A. This is correct. To find the DC steady state solution for this circuit, ...
Alfred Centauri's user avatar
9 votes

What happens to an inductor if the stored energy does not find a path to discharge?

Usually this extra energy creates a spark due to the high back emf produced. But it is not always possible for a coil to create sparks. It is clear If we try out the experiment. So what happens to ...
Rishab Navaneet's user avatar
8 votes

If induced voltage (back-emf) is equal and opposite to applied voltage, what drives the current?

The answer to your question lies in the fact that you are dealing with two different types of electric field (conservative and non-conservative) and that the non-conservative electric field owes its ...
Farcher's user avatar
  • 96.2k
8 votes

Is it safe to apply Kirchhoff's voltage law to a closed loop containing an inductance with unsteady current?

Yes, the Kirchhoff Voltage Law (KVL): Sum of voltages (here, meaning potential drops) across all elements connected via perfect conducting wire in series in to a closed circuit is zero. is valid for ...
Ján Lalinský's user avatar
8 votes
Accepted

Confusion in understanding the behavior of inductor in RL circuit with DC source

When we have a DC voltage source with a switch in series with RL and the switch is closed at t=0 then it is said that current is zero initially, but the voltage across inductor is same as that of ...
BioPhysicist's user avatar
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8 votes
Accepted

Deforming LC circuit into dipole antenna

First, let me urge you to do some experiments. Physics is physical: it relates to real phenomena in the real world. Textbook physics is a poor substitute for real world physics. These days, this ...
John Doty's user avatar
  • 21k
8 votes

If inductors block AC then how are they used In LCR circuits?

Saying inductors block AC is like saying resistors block current. It doesn't mean that inductors don't permit any AC current at all. In particular, I'm not sure why you think an AC voltage applied to ...
Puk's user avatar
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8 votes
Accepted

Does the unit "volt-seconds" have any interesting interpretation?

The volt-second is the weber, the SI unit of magnetic flux. Applying 1 volt across an ideal inductor for 1 second increases its flux by 1 weber.
Puk's user avatar
  • 13.5k
7 votes

Why is all of the energy from a battery stored on an inductor but only 50% on a capacitor?

however I can't think of the fundamental reason as to why it is completely impossible to charge a capacitor with anything but 50% of the battery energy whereas an inductor could theoretically ...
Alfred Centauri's user avatar
7 votes
Accepted

Inductor and Capacitor with a DC supply

Assuming that there is no resistance in the circuit the current in the circuit will be given by the equation $I(t) = \mathcal E \sqrt {\frac CL} \sin \omega_0 t$ where $\omega_0 = \sqrt\frac {1}{LC}$. ...
Farcher's user avatar
  • 96.2k
7 votes

Why complex numbers are used in electronics?

Using imaginary numbers for current in reactive components just happens to make the maths a lot simpler. In AC circuits there is typically some phase difference between the voltage and the current. ...
Guy Inchbald's user avatar
  • 7,382
7 votes

What happens to an inductor if the stored energy does not find a path to discharge?

An important point which is somewhat addressed by others but perhaps not clearly enough is (quoting Scotty) "Y' canna break the laws of Physics". You can make everything ideal - semiconductor wire, ...
Russell McMahon's user avatar
7 votes

Where does the energy stored in inductor go on opening the switch?

TL; DR: Every real circuit has a capacitance, hence decaying RLC oscillations. General points There are two general points to learn from this question: Every model in physics (and beyond) has its ...
Roger V.'s user avatar
  • 58.8k
7 votes

How does current flow in a purely inductive circuit if the net voltage is zero?

How does current flow in a purely inductive circuit if the net voltage is zero? The problem in this question is that it is based on a completely wrong assumption. This concept of “net voltage” isn’t ...
Dale's user avatar
  • 100k
6 votes

Why do magnetic coils consist of many thin wires?

If you have a single tube, the current will flow on it directly without making the $N$ loops. It will result a different direction, i.e. different magnetic field, its magnetic field will be much ...
peterh's user avatar
  • 8,221
6 votes
Accepted

Magnet falling through a coil that does not form a circuit. Am I wrong or is the mark scheme?

The break in the circuit will stop electrons from flowing, but it does not stop the EMF from being induced. The EMF is simply canceled out by the electrostatic forces which prevent the electrons from ...
J. Murray's user avatar
  • 69.2k
6 votes

Inductor and Capacitor with a DC supply

Since you want to avoid differential equations, I will instead consider the so-called Phasor domain, which is actually nothing but the Fourier transform of the original signals. In phasor domain, we ...
SonerAlbayrak's user avatar
6 votes

Why doesn't the potential difference across an inductor increase over time?

Therefore, current will increase, and voltage will also increase across the entire circuit. It's not clear exactly what you mean by "across the entire circuit", but think about your model of a ...
The Photon's user avatar
  • 27.6k
6 votes

Why do we not have devices like inductors or capacitors to hold gravitational field?

It's not really true to say that a capacitor stores an electric field, or an inductor stores a magnetic field, though there are certainly fields associated with both. I think a better way of putting ...
John Rennie's user avatar
6 votes
Accepted

Does a charged capacitor weigh more than uncharged?

Your reasoning is correct. If you store energy in a system, mass-energy equivalence provides the conversion for calculating the matter equivalent which, if you had a weighing device sensitive enough, ...
niels nielsen's user avatar

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