Imagine looking at a solenoid from above. Current passing is through it in a clockwise direction. The direction of the field lines therefore is towards the bottom of the solenoid.
Now pass a straight current carrying wire through the central axis of the solenoid. The current in the wire is travelling in a downward direction so the field around it is going in a clockwise direction if viewed from above.
My question now is how do the field lines interact, and is there any resultant force on the wire?
My attempt at thinking this through says that the field lines of the solenoid and wire will become downward spiralling field lines.
Using this I believe that the wire will experience force in the upward direction.
Is this correct?