Questions tagged [lenz-law]
73 questions
8
votes
4 answers
Could Faraday-Lenz law be understood from forces rather than from flux?
Picture a magnet passing through an spiral wire. Because of Faraday-Lenz law we know that the change of flux on the spiral wire will create eddy currents inside of it (this currents will create a magnetic field that goes against the increasing…
Álvaro Rodrigo
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7
votes
1 answer
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! ). But this does not happen in our houses…
Aghila C C
- 93
6
votes
1 answer
If a loop is not complete, and magnetic field passing through it is changing; will their be emf induced in the loop?
In a setup like the one show in the figure:
Will there be an induced EMF across the loop(given that the field is increasing)?
(my dilemma is : since the loop is not complete, we cannot define the flux through it.)
Is it valid to define Flux for an…
Ash_Tag
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5
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1 answer
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" graph.
However, our data resembles a stairway instead.
The…
Valdemar
- 51
4
votes
1 answer
Is diamagnetism really related to lenz's law?
I've visited multiple resources and read a lot of questions here on the nature of diamagnetism. I still don't understand if it truly has anything to do with lenz's law. In Walter Lewin's electromagnetism lectures, he says that this is wrong. It has…
EM_1
- 924
3
votes
2 answers
Lenz's law, does magnetic flux as measured in Tesla decrease when current is induced?
Wikipedia defines Lenz's law as that the magnetic field created by the induced current opposes changes in the initial magnetic field,
"Lenz's law states that the direction of the electric current induced in a conductor by a changing magnetic field…
BipedalJoe
- 171
3
votes
2 answers
How to explain different voltage and symmetry?
Imagine a magnet is falling along the axis of a uniform metal ring, there is an Eddy current in the ring due to changing magnetic flux and the direction of the current is determined by Lenz's law. Take two points on the ring on each end of the same…
Ebi
- 1,148
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3
votes
2 answers
Why does a changing magnetic flux induce an EMF in "opposite direction"?
Faraday's Law of Induction tells us that a changing magnetic flux induces an EMF in the conductor, causing an electric current to flow.
By Lenz's Law, we get the direction of induced EMF which turns out to be in the opposite direction of the…
Shriesh Kumar
- 133
3
votes
2 answers
Induced voltage difference in a magnetic field
I'm pretty new to electrodynamics, and I was wondering whether someone could help me with the following problem:
A thin conducting rod with length $\ell$ rotates at rate $\omega$ in a uniform magnetic field.
(a) If the magnetic field $B$ is constant…
user278976
3
votes
1 answer
Lenz' law and magnetic moment
Lenz Law says that the induced current will circulate in a direction such that it produces a magnetic field that is opposite to the change of applied magnetic field. For example, if the loop is a circle on the screen, and the applied magnetic field…
Dragon123
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2
votes
2 answers
Induced E.M.F without changes in magnetic flux
When we move a wire upwards through a uniform magnetic field, the magnetic flux does not change. If we consider the equation for magnetic flux which is:
ΦB = B ⋅ A = BAcosθ
The magnetic field is uniform so B is the same and A certainly did not…
Sher
- 67
2
votes
4 answers
Does the direction of coil winding impact the direction of induced voltage?
In Case 1) and Case 2) (see the image below) induced current is flowing counterclockwise (from the magnet's POV) if we move the magnet towards the coil (and the circuit is closed, obviously).
However I'm not so sure about the direction of the…
gvg
- 25
2
votes
2 answers
No EMF generated on a loop lying outside changing $\vec B$ (but $\vec E ≠ 0$)
If we establish a changing magnetic field in a region of space, circular electric field lines are induced. This electric field extends even after we exit the region of the magnetic field. If a closed path lies completely outside the magnetic field…
Dodo
- 627
2
votes
4 answers
Question on Lenz law
According to Lenz's law , the direction of current induced in a coil is such that it opposes the very cause which produce it
Why is this so?
Vaibhav Tiwari
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2
votes
1 answer
Weight of Diamagnetic Objects in Lenz Effect
I've seen the simple experiment of dropping a neodymium sphere down through a copper or aluminum tube where it falls at less than g. The "Lenz Effect"
My question is:
Has there ever been an experiment when the NeoD sphere is tied to a string…
ClancyJohn
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