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@aarthivg • 15 Apr, 2012
Today, one of our lecturers asked this question in classroom. It was - What is the magnetic equivalent of ohm's law? I am clueless about the answer to this. Can some CEan explain?
@silverscorpion • 15 Apr, 2012 • 1 like Ohm's law:

E = IR where E is the EMF, I is the current and R the resistance.

Hopkinson's law

F = ΦR[sub]m[/sub] where F is the MMF, Φ is the magnetic flux and R[sub]m[/sub] the magnetic reluctance

Just as Ohm's law relates the EMF across an element in a circuit to the current flowing through that element, Hopkinson's law relates the MMF (MagnetoMotive Force) across a magnetic element in a circuit to the magnetic flux through that element. The constant corresponding to electrical resistance in Ohm's law, is magnetic reluctance in Hopkinson's law..
@aarthivg • 15 Apr, 2012
silverscorpion
Ohm's law:

E = IR where E is the EMF, I is the current and R the resistance.

Hopkinson's law

F = ΦR[sub]m[/sub] where F is the MMF, Φ is the magnetic flux and R[sub]m[/sub] the magnetic reluctance

Just as Ohm's law relates the EMF across an element in a circuit to the current flowing through that element, Hopkinson's law relates the MMF (MagnetoMotive Force) across a magnetic element in a circuit to the magnetic flux through that element. The constant corresponding to electrical resistance in Ohm's law, is magnetic reluctance in Hopkinson's law..
Actually this question was asked in an exam.
the options are
lens law
rowlands law
maxwells law
@silverscorpion • 15 Apr, 2012 ^^ Then the answer would be Rowland's law.. It seems Hopkinson's law is also called Rowland's law.

In that same Wiki page, there is an analogy of various elements in magnetic and electric circuits. Refer that..
4.1k views

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