All Questions
Tagged with electromagnetism inductance
44
questions
11
votes
3
answers
9k
views
When mutual inductance is occurring between two coils, is self inductance always occurring in each individual coil?
When a coil connected to an AC generator creates an EMF in another nearby coil (mutual inductance), is self inductance simultaneously occurring in both coils?
- 545
10
votes
3
answers
3k
views
Does a thermal inductor exist?
There is an analogy between electric and thermal circuits.
A voltage difference is equivalent to a thermal difference.
$$\Delta V \equiv \Delta T$$
Electric charge $q$ is equivalent to heat $Q$.
...
- 281
6
votes
2
answers
1k
views
Why is all of the energy from a battery stored on an inductor but only 50% on a capacitor?
I am learning about inductors and capacitors and we derived the energy stored on a capacitor to be 50% of that delivered by the battery. We did this considering a circuit of a capacitor connected to a ...
- 3,997
4
votes
2
answers
3k
views
Why does the current increase in an LC circuit while the capacitor is being discharged?
From the maths governing an LC circuit (eg. $E_B=\frac{LI^2}{2}$) we can deduce, that the current through the inductor will have a maximum value, when there's no energy stored in the capacitor, or ...
- 773
4
votes
2
answers
6k
views
Magnetic moment of an iron-core solenoid
I'm currently developing a Simulink model for the attitude control system (ACS) of an undergrad-developed CubeSat. The ACS uses magnetorquers for attitude actuation.
The magnetorquers are iron-nickel ...
- 93
4
votes
1
answer
48k
views
Magnetic field due to a coil of N turns and a solenoid [duplicate]
I have learnt that the formula for calculating the magnetic field at the centre of a current-carrying coil of $N$ turns is:- $$ B = \frac {\mu N I}{2r}$$
(where $r=$ radius of the loop,
$I=$ current ...
- 197
4
votes
5
answers
2k
views
Isn't the inductor equation negative?
The inductor "resists" change in current. So say you measure the voltage across the inductor from point A to point B - the current is flowing in from A towards B. Now say the current is increasing. ...
- 2,009
3
votes
3
answers
1k
views
Kirchhoff law and Inductors
I am struggling with using Kirchhoff's rule in circuits with Inductors. Looks like if you have an inductor, we have Electric field (E) that is created using a time varying magnetic field and that E is ...
- 1,481
3
votes
2
answers
246
views
Using Faraday's law twice
I have trouble understanding Faraday's law when there is an induced current which in turn induces another current in the same circuit. I shall illustrate my confusion with an homework problem and I ...
- 963
2
votes
1
answer
153
views
Quantization of a waveguide: he only has one of the two E.O.M in his Lagrangian. How can the quantization be correct?
I am following this reference, appendinx C and D, around page 61
The goal is to quantize electric of current of propagating wave in a waveguide.
Classical E.O.M:
We model a waveguide by a ...
- 1,450
2
votes
4
answers
250
views
Inductor connected to an AC source
Consider an inductor connected to an AC source, $V=V_0\sin\omega t$.
Let the the switch in the circuit be closed at $t=0$. Then by Kirchoff's voltage law,
$$
V-L\frac{dI}{dt}=0
$$
where $I$ is the ...
- 23
2
votes
3
answers
534
views
Why can't the current in a solenoid be changed rapidly?
Why can't the current in a solenoid be changed instananeously? My reasoning is since the current in a solenoid is given by a integral:
$$I(t) = \frac{1}{L} \int_{t_0} ^{t_f} V_Ldt$$
then if $t_f = t_i ...
- 548
2
votes
3
answers
644
views
How is EMF still induced in an incomplete/open circuit?
I understand that current can't flow through a coil if it is not complete, but surely this means that if a magnet is dropped through the coil, no EMF would be induced either, since work is done when a ...
- 31
2
votes
1
answer
290
views
Mutual inductance - induced magnetic flux in the primary
Let there be two coils, L1 (with self inductance L1), and L2, with self inductance L2.
The first coil is connected to a sinusoidal supply, and the second one is connected to a resistor load, as shown ...
- 21
2
votes
1
answer
1k
views
How do I show for an ideal transformer $M^2=L_1L_2$?
I've been stuck on this problem for about an hour.
In an ideal transformer, the same flux passes through all turns of the primary and of the secondary . Show that in this case $M^2=L_1L_2$, where $...
- 5,371