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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 ...
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" ...
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 ...
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 ...
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 ...