All Questions
33
questions
0
votes
2
answers
73
views
Cannot catch a minus sign mistake when deriving the ODE for an LC circuit
It's probably a very basic question but I just cannot wrap my mind around it. I'll just try to derive the differential equation for an LC circuit:
According to the law of induction, in a solenoid we ...
- 4,887
0
votes
2
answers
68
views
Maximum Impedance for LCR series circuit
Impedance of an LCR series circuit can be maximum when either Inductive Reactance or Capacitive Reactance is maximum at an instant of time.
Max Capacitive Reactance is at minimum frequency, and max ...
0
votes
1
answer
53
views
Why doesn't current flow stop in LC oscillation?
Why doesn't current flow stop in a LC circuit? It is supposed to stop when the magnitude of emf developed across capacitor is the same as the inductor, right?
1
vote
2
answers
78
views
Telegraphers' equations for lossy transmission line when $R$, $L$, $G$, and $C$ are frequency dependent
The telegraphers' equations are commonly written as
$$\frac{{\partial v(z,t)}}{{\partial z}} + R\space i(z,t) + L\frac{{\partial i(z,t)}}{{\partial t}} = 0$$
$$\frac{{\partial i(z,t)}}{{\partial z}} + ...
- 11
2
votes
1
answer
67
views
Does parasitic capacitance contribute to the magnetic flux?
When modeling a real inductor, typically the equivalent circuit is the following one:
Source
A series resistance and parallel capacitor is added.
This model works very well to explain the following ...
- 187
2
votes
5
answers
109
views
Magnetic field in a capacitor in a $LC$ circuit
Consider a simple $LC$ circuit in which the charge on the capacitor varies sinusoidally. Current flows in this circuit, changing the charge on the capacitor and hence changing the electric field ...
- 29
3
votes
0
answers
194
views
Wave equation derivation in a transmission line
$$
V(x, t) = L\Delta x\frac{\partial I}{\partial t}(x, t) + \frac{1}{C \Delta x}\int{I_c(x, t) \; dt} \tag{1}
$$
$$
V(x + \Delta x, t) =\frac{1}{C \Delta x} \int {I_c(x, t) \; dt} \tag{2}
$$
$$
I(x) = ...
- 1,525
2
votes
1
answer
123
views
Why is the product of the $L$ and $C$ matrices for coupled transmission lines diagonal?
Background - transmission line
$\newcommand{\ket}[1]{\left \lvert #1 \right \rangle}$
A transmission line can be modeled as an infinite sequence of inductors and capacitors:
...
- 24.6k
1
vote
1
answer
248
views
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:
$$i_C = \omega CV \ cos(\omega t + \pi/2) = -\omega CV \ sin(\omega t)$$
...
- 111
0
votes
1
answer
99
views
Work done by battery [closed]
In charging a capacitor to a charge $Q$
Is there an equivalent to this in setting up current through an inductive circuit?
Energy stored in inductor $= 1/2Li^2$
What would be the work done in setting ...
- 3
1
vote
2
answers
515
views
What is the amplitude of current in LC oscillations
Since there is no resistance in an LC circuit (not attached to an AC source), what's stopping the current from rising to infinite. And if resistance is provided by the inductor by self induction, then ...
- 105
1
vote
2
answers
254
views
Relation of electric permittivity $ε_{0}$ and magnetic permeability $μ_{0}$ of vacuum space with capacitance $C$ and inductance $L$ of matter?
I am asking if the permittivity and permeability constants of vacuum space controlling propagation speed of electromagnetic energy, light, through vacuum space:
$$c=\frac{1}{\sqrt{\varepsilon_{0} \mu_{...
- 4,170
0
votes
0
answers
36
views
Are Idealized Transformers Realizable?
Since parasitic capacitance in an inductor is always in parallel with its inductance, would this effectively become analogous to magnetic remanence exhibited within rebars (made from carbon steel) ...
- 1
0
votes
0
answers
12
views
How to find the canonical equations of the series RLC circuit? [duplicate]
First, I consider the LC circuit with an ion in the capacitor, which is like this:
The current $I$ can be derived easily using Shockly-Ramo theorem
\begin{equation}
I = -\frac{qp}{dM} + C\dot{U} \ \ ...
- 68
0
votes
0
answers
111
views
How to find the canonical equations of the RLC circuit
First, I consider the LC circuit with an ion in the capacitor, which is like this:
The current $I$ can be derived easily by using Shockly-Ramo theorem
\begin{equation}
I = -\frac{qp}{dM} + C\dot{U} \...
- 68