Magnetic lines of force surrounding two parallel conductors carrying current in opposite directions?

Question

magnetic lines of force surrounding two parallel conductors carrying current in opposite directions. If they were free to move, would the conductors move together or move apart?

Answer 1

It would depend which way the wind was blowing.

Magnetic lines of force in conductors won't cause the conductors to move.  

Answer 2

They will move apart due to the superposition of the magnectic field in between them.

Due to the tendancy to equalise the forces on the wires, if they are free to move then they will.

This is the same physics behind electromagnets.  It is an issue in large transmission lines too which is one reason why they have specified distances between them.