# Questions tagged [inductance]

The property of an electrical conductor through which a change in current through it induces an electromotive force in both the conductor itself as well as in any nearby conductors by mutual inductance. Also use more broadly for electromagnetic phenomena in solenoids.

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• 361
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### Magnetic flux inside solenoid

Suppose that I have a small coil that is moved at a steady rate into a solenoid. The solenoid already has a current passing through (basically, it is an electromagnet). The small coil starts beyond ...
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### In series RLC circuit, does decreasing the capacitance value really make the circuit more capacitive circuit?

This seems very counter intuitive to me. How can decreasing the capacitance value make the circuit more capacitive ? The math tells me so : If $C$ decreases then $X_c = \dfrac{1}{\omega C}$ ...
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### Does there exist a rigorous general mathematical proof for $M <\sqrt{L_1L_2}$?

Does there exist a rigorous general mathematical proof for $M <\sqrt{L_1L_2}$? Here $M$ is the mutual inductance between two conductors and $L_1$ and $L_2$ are their respective self-inductances. (...
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### Why is the electric field inside a solenoid tangential?

I have been looking at some derivations for the electric field inside a solenoid. I know how to find it, but I don't get the symmetry argument used. This is often of the form: Since if we choose a ...
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### Calculating magnetic field strength for a very small electromagnet

I am trying to calculate the magnetic field (in tesla/gauss) of an electromagnet that is very small and has very few windings. For example 12 windings over 0.003 meters. I know this is not going to ...
• 301
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### How Are Electromagnetic Waves Produced?

How EM waves are produced say by a capacitor of an LC circuit here if $E$ is increasing in upward direction? My thoughts Thought 1:- If E is increasing E flux is increasing thus B field must be ...
1 vote
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### Back EMF in electromagnetic coil

I am trying to quantify the back EMF generated while actuating an electromagnetic coil, this would be included in a general calculation to estimate the coil output under a variety of conditions. My ...
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1 vote
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### Equation relating the current carried by a solenoid to the force experienced by a magnetic dipole?

I am trying to find an equation or a series of equations that relates the current I carried by a solenoid of length L with turns N to the force F experienced by a magnetic dipole of strength M that ...
1 vote
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### Coilgun projectile force calculation

Please excuse me if I am completely wrong because I am a 9th grader but I hopefully am able to explain briefly about my problem. I was trying to create a function to calculate the Force of an iron ...
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### What exactly is the formula of total flux linkage? Is it $dλ=dΨ *\frac{\text { Ienclosed}}{I}$ or $λ=N*Ψ$?

In Sadiku, he used the formula $dλ=dΨ *\frac{\text { Ienclosed}}{I}$ to determine the total flux linkage for coaxial cable for $ρ<a$ and for $a<ρ<b$, but I applied this formula for the ...
1 vote
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### In an $RLC$ circuit, where there are multiple components instead of a single resistor/inductor/capacitor how does impedance $Z$ is calculated?

If there is an $RLC$ circuit where some components are in series with one another and some components are in parallel with one another, how does the total impedance of the circuit is calculated? I ...
1 vote
42 views

As the magnet moves from the outside, the magnetic flux that is linked to the circuit is [pi_0 sin(wt)]. We have listed a series of processes related to electromotive force, self-inductance L, and ...
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### What is the flux linkage or inductance or induced voltage per unit length of the hollow tube conductor surrounding the inner conductor?

What is the flux linkage or inductance or induced voltage per unit length of the hollow tube conductor surrounding the inner conductor in some section due to the current in the inner thin conductor? ...
1 vote
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### Does the presence of a disconnected coil nearby affect the self-inductance of a coil under test?

Picture two coils in close proximity. They have the same dimensions and are located co-axially, with a small gap between then (like Helmholtz coils, but much closer together than in the standard ...
• 111
1 vote
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### Current through a capacitor in AC Circuits

I'm a little confused on the equation for the instantaneous current through a capacitor in AC circuits. My textbook has it as: $$i_C = \omega CV \ cos(\omega t + \pi/2) = -\omega CV \ sin(\omega t)$$ ...
1 vote
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### Inductance of a coated cylinder

Say we have an infinite cylinder, through which a current of intensity $I$ flows. Say this cylinder is coated with a conductive material, of negligible thickness, through which a current of the same ...
1 vote
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### Are we always allowed to treat an inductor as a battery with the same voltage?

When there is an induced emf, Kirchhoff's Loop Rule no longer is true, because electric fields are nonconservative when there is an induced current, as stated by Faraday's Law: However, I have seen ...
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### Why is the relation between voltage ratio and frequency a linear one in a lumped transition line?

In an experiment the cutoff frequency of a lumped transmission line is determined by measursing the ratio of the output/input voltages. The lumped transmission line is a ladder network of 40 ...
• 1,047
1 vote
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### Question about the impedance of a RLC circuit

I made an experiment with a RLC circuit, and I found the resistance, the capacitance, and the inductance with measures. So I decided to calculate the impedance of the circuit, depending on the ...
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### Definition of inductance and volume currents

If I have a uniform, infinitely thin current. The relationship between inductance and current by definition is: $\phi_{B} = L I$ Where inductance($L$) the proportionality constant between a wires ...
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### Do transformers return current to source when magnetic field collapse at primary coil?

When we close the circut containing an inductor and a battery, the current starts flowing, which builds magnetic field around inductor, changing magnetic field produces its own current in opposite ...
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• 557
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### Crossover filter gives weird results

I was analyzing results of an experiment on a crossover filter and I was trying to take into consideration the parasitic resistance of the inductor L (called $R_L$). I know the theoretical crossover ...
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1 vote
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### Two questions about an AC electric circuit: Have I interpreted the dots correctly and where does the negative sign come from?

So I am looking at two mutually coupled circuits that are not at resonance. In particular I am looking at a pair of electric circuits discussed on pgs: 259 - 261 of the book "Electricity and Magnetism"...
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### Velocity of an Object Accelerated by an Inductor

I am currently trying to build a coil gun as a class project (for an introductory programming/electronics class), and I want to be able to determine the launch angle necessary to send an object a ...
1 vote
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### Transformers and basic inductor physics

1) Why does resistor reduce the lag in a RL circuit? I understand why current lags by 90° with the voltage across the inductor. (After watching this) But I don't understand why that lag, would be ...
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### Confusion regarding inductor connected to an AC source

Suppose I connect an inductor to an ac source. Now a time varying current is produced and this causes change in magnetic flux linked with inductor coils and hence an induced is generated. But why ...
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### Energy Stored In Superconductor

I have two questions regarding this topic: What is the equation to calculate the energy stored in a superconductor when you apply a current. I’ve been looking it up and have been getting ...
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### Understanding simple $LC$ circuits
I'm trying understand the physics of simple inductor-capacitor circuits such that there is just an inductor $L$ and a capacitor $C$ and a switch. Imagine first that the capacitor is fully charged and ...