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magnetic induction question

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fonograph:
I know that moving conductor in magnetic field will cause current to flow in that conductor.But what happens if the conductor is moving perfectly straight,parallel to the direction of magnetic field,its cruising along the lines.

Will that cause current to flow too?  I saw video about induction that says cutting the magnetic lines causes the current flow,does that mean not cutting the line,going alongside them,will no induce current?

cdev:
there would be positions and orientations where a moving electromagnetic field did not induce any voltage in a conductor, that is the same thing as  equilibrium, this would be called a null in its pattern. Perpendicular wires in an open space only exhibit very low amounts of coupling to one another.

ejeffrey:
That is correct, moving parallel to the applied field will not introduce an emf  or current flow.  The force on an electron is V x B.  If V and B are parallel the force is zero.

In addition, In the case of a wire (as opposed to an arbitrary shape), if the velocity or the magentic field is parallel to the wire, the emf will be perpendicular to the wire, and won't cause any current to flow along the wire.

Keep in mind that when we talk about magnetic induction, wires are normally loops.  So you have to consider the entire loop to see if there is induced current.

fonograph:
What is V and B?

IanB:
A slightly related question:

Suppose there is a transformer which has a closed magnetic loop inside the core (e.g. a toroid). I been given to understand that the (changing) magnetic field lines should intersect the conductor for a current to be induced. If, in a toroid, the magnetic field lines are concentrated within the core, how is current induced in the secondary windings of a toroidal transformer? If you passed a DC current through a winding to turn the transformer into an electromagnet, would there be any detectable magnetic field on the outside? If so, where would the north and south poles be?

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