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Entanglement
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The title is enough
jtbell said:Look at the list of "Related Discussions" at the bottom of this thread, and you'll find two threads with the same question as yours. One of them has 24 responses, which looks promising!
I know the observation, but I can't figure out its reason. Bio-Savarts law will only guide me to the direction of the field mathematically not logically nor intuitively.UltrafastPED said:It's an experimental observation, first made in 1820. See http://inventors.about.com/od/lessonplans/ht/magnetic_fields.htm
The Biot-Savart law was inspired by this and other observations.
See http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/biosav.html
So you should be able to start with the Biot-Savart law, and get back to Oersted's observation.
How isn't it a physics question if I want a deeper answer??WannabeNewton said:It's simply due to the cylindrical symmetry of the system.
ElmorshedyDr said:I know the observation, but I can't figure out its reason. Bio-Savarts law will only guide me to the direction of the field mathematically not logically nor intuitively.
ElmorshedyDr said:Why isn't there any poles
Why are the lines rotating around the wire and not ending or beginning at certain poles ?
Thanks a lot !jtbell said:Here's an argument that the magnetic field around a straight wire has to be in circles simply because of the symmetry of the source:
https://www.physicsforums.com/showthread.php?p=4711973#post4711973
What does it mean that circumference is directly proportional to the intensity ? Since there are infinite concentric circlesmfb said:2πr is just the exact circumference of a circle with radius r.
There is nothing "maximal". The (theoretical, ideal) field extends to infinity.
That is a weird way to reduce Ampere's law.
mfb said:As I said, that is a weird way to reduce Ampere's law. You could read it "with larger current, you get the same field strength (which you omitted) at a larger radius".
And constant factors like 2π are irrelevant anyway if you look at proportional quantities.
Yes.ElmorshedyDr said:I think Br [itex]\propto[/itex] [itex]I[/itex] seems more meaningful
their product is directly proportional to the intensity
?ElmorshedyDr said:how is B at the center of a circular loop and a solenoid derived from :
Ampere's circular law
B = [itex]\mu[/itex][itex]I[/itex] [itex]/[/itex] 2[itex]\pi[/itex]r
The magnetic field of a wire is circular because of the right-hand rule. When current flows through a wire, it creates a magnetic field that wraps around the wire in a circular shape. The direction of the magnetic field is determined by the direction of the current flow, following the right-hand rule.
The circular shape of the magnetic field is caused by the flow of current through the wire. When current flows through a wire, it creates a magnetic field that wraps around the wire in a circular shape. This circular shape is a result of the interaction between the electric current and the magnetic field.
Yes, the strength of the magnetic field does affect its circular shape. The strength of the magnetic field is directly proportional to the current flowing through the wire. Therefore, the stronger the current, the stronger and more pronounced the circular shape of the magnetic field will be.
Yes, the circular shape of the magnetic field can be changed by altering the current flow through the wire. Changing the direction or strength of the current will result in a change in the direction or shape of the magnetic field. Additionally, external magnetic fields or the presence of other conductors can also affect the shape of the magnetic field.
Yes, the circular shape of the magnetic field is present in all wires when current flows through them. This is a fundamental principle of electromagnetism and is applicable to all wires, regardless of their size or material. However, the strength and shape of the magnetic field may vary depending on the properties of the wire and the current flowing through it.