There will be an induced current in the loop in this case.
The magnetic field lines don't have to coincide with the loop. All that
is necessary
is for the magnetic flux to change inside the loop, which would be true
here.
Another way to look at it is that the changing magnetic field will induce
an electric field
at various points in space (not just where the magnetic field is). The
induced electric field at the location of the loop will drive a current in
the loop.
Steven T. Ratliff
Professor of Physics
Northwestern College
3003 Snelling Ave. N.
St. Paul, MN 55113-1598
U. S. A.
Internet: stratliff@nwc.edu
"Fakhruddin, Hasanbhai" <hfakhrud@BSU.EDU>
Sent by: "phys-l@lists.nau.edu: Forum for Physics Educators" <PHYS-L
04/12/02 11:02 AM
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Subject: EM Induction - A conceptual question
Hello everyone!
This question has nagged me for some time. I will appreciate your
indulgence in this.
Imagine a circular loop of wire of radis R. A uniform magnetic field is
distributed perpendicular to its surface and confined to a concentric
circle of radius r < R.
Will the change in the magnetic field strength induce a current (emf)
in the loop?
By the Faraday's law there should be an emf induced becuse of changing
flux. However, my contention is that B-field lines are not "physically"
linked to the loop. Why should changing field affect anything in the
loop?