Iron wire, Copper wire (spare lead), Connecting wire with crocodile clips, Bar magnet, 9V battery
(1) Make two iron wires straight as possible as you can.
(2) Paste them parallel to each other with tape.
(3) The distance between two wires is about 4 cm.
(4) Connect each iron wire to a 9V battery.
(5) Put one spare lead or a thin aluminum pipe on the both iron wires vertically.
(6) Bring the N-pole under the aluminum pipe.
When two iron wires are connected to the battery as shown fig,3 and you bring the north pole of the magnet close to the spare lead, in which direction will the lead move ?