Q. What property is displayed when two circuits are arranged so a changing current in one causes an emf
in the other circuit.
Shown below are two conductors, A and B. Conductor A is connected to a battery through a switch (S1).
Conductor B is near conductor A, but is not connected to any voltage source. A meter is installed in series
with conductor B and indicates any current flow in conductor B.
When the switch is closed, current builds up in conductor A. Lines of magnetic flux expand around
conductor A and conductor b, as shown in the following drawing. A voltage is induced in wire B. The
direction of the induced voltage in conductor B is determined by the left hand rule for generators. The
current in conductor B is opposite in direction to the current in conductor A at the point of induction.