All Questions
Tagged with electromagnetism inductance
385
questions
2
votes
1
answer
237
views
How can we define the energy stored in a (conservative) force field?
I have come to know from my textbook that energy is stored in the E-field of a capacitor, in the B-field of an inductor and so on. Take the example of an inductor. The derivation bewilders me ...
- 380
0
votes
4
answers
1k
views
Spherical magnet inside a solenoid
When passing a bar magnet through a long solenoid why is it that the induced emf when the magnet is in the middle of the solenoid is zero? And if a spherical magnet is put inside the solenoid, will ...
- 27
0
votes
1
answer
98
views
Confusion regarding inductors
I understand that a change in flux linkages of an inductor results in induced emf across it, the magnitude and direction of which can be determined by Faraday's and Lenz's laws. The magnitude of this ...
- 1
0
votes
1
answer
205
views
How much does the magnetic force change in a solenoid with the distance between turns?
I was looking for answer in my physics book and in Internet but not. I guess that more distance should be an smaller magnetic field but I do not know how much.
- 3
1
vote
0
answers
212
views
Mutual inductance theoretically decreasing while EMF is increasing in 2 square coil system
I have a quick question regarding electricity and magnetism. I am measuring the induced emf in a square coil of wire with an inductance of 439uH (the other coil is also 439uH and is the same shape). I ...
- 123
2
votes
1
answer
7k
views
Transformers - Why more coils in second coil causes more voltage [duplicate]
I am learning about magnetic induction and transformers.
I have coil1 which uses AC to create an oscillating magnetic field.
I have ...
- 153
4
votes
5
answers
49k
views
What is the difference between electromagnet and solenoid?
What is the difference between electromagnet and solenoid? Both these terms seem as the same thing to me. The only difference that I can find seems to be that an electromagnet contains a soft iron ...
- 179
1
vote
2
answers
1k
views
Find magnetic field in a solenoid for different regions? [closed]
Problem statement:
A steady current I flows along an infinitely long hollow cylindrical conductor of radius $R$. This cylinder is placed coaxially inside an infinite solenoid of radius $2R$. The ...
2
votes
3
answers
9k
views
${}$Self-induction in transformer
Wont self-induction ruin the working of a transformer?
While increasing voltage (AC) in the primary coil, wont there happen a self induction in the primary coil itself?
$$E_0 = -L \frac{dI}{dt}.$$
If ...
- 908
1
vote
1
answer
64
views
Can two transformers used to make tesla coils?
Tesla coils seem to perform the same as a transformers: they use two coils and use magnetic field to transfer the energy. Doesn't using two transformers produce the same result? It doesn't seem to be ...
- 31
2
votes
2
answers
563
views
Why do old transformers make sounds, but new ones don't?
What I think is that maybe insulation is gradually removed between plates, and eddy currents start passing from one plate to another and this produces sound. Am I right?
- 71
0
votes
2
answers
282
views
Is there any theoretical reason behind multiplying by $N$ when using Faraday's law of induction?
It is a well known fact that whenever we want to calculate the emf in a solenoid we usually multiply the changing flux for one loop times $N$, which is the number of turns in the solenoid.
But why is ...
- 1,619
1
vote
1
answer
110
views
How to model the impedance of a coil with a dielectric slab on the top
I have sketched what I meant in the image below. Were there no dielectric slab, the coil could have been simply modeled as an inductor. But I am not sure what the impedance can be if there is a ...
- 161
1
vote
3
answers
19k
views
Why in a solenoid, do the magnetic field lines resemble that of a bar magnet?
Each loop in the solenoid will have its own magnetic field wrapped around it. In that case it won't resemble the magnetic lines formed by a bar magnet...; but we see that it is the same. Why is that?
- 494
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