All Questions
7
questions
1
vote
1
answer
45
views
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 ...
5
votes
1
answer
533
views
Current through a solenoid: magnetic field gives a staircase graph
We were running current through a solenoid coil with an iron core, and measuring the resultant magnetic field strength. We expected a purely linear relation for the "current-field strength" ...
7
votes
1
answer
540
views
Is Back EMF produced in household wires?
Since we use AC for domestic purpose, shouldn't Back EMF (Counter-EMF) be produced in household wires? If yes, then the output voltage in the appliances will be less (that's what my stupid brain says! ...
0
votes
1
answer
127
views
What provides energy in mutual inductance to unconnected coil
In this mutual inductance setup:
when current is passed through coil 1 the flux through coil 2 changes for a short amount of time which induces a current in coil 2 the direction of which, in ...
1
vote
2
answers
1k
views
How can we derive the polarity of the induced voltage in an inductor?
As we know, the voltage-current relation of a two-terminal constant-inductance inductor is:
$v_L(t) = L \, \dfrac{\mathrm di_L(t)}{\mathrm dt} \tag 1$
I've managed to prove that equation without ...
2
votes
2
answers
1k
views
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 ...
0
votes
2
answers
2k
views
Misunderstanding of Lenz's law
The increasing current (and hence increasing flux and changing magnetic field) in the outer solenoid induce a current in the inner solenoid.
The current in the outer solenoid produces a magnetic ...