Refer to the diagram attached herewith.
The orange line indicates the magnetic field. As u can see it is in a circular form, Now, here u have to use the flemming's left hand rule.
However, as the magnetic field is in circular form u have to choose one point to apply the Left hand rule. The red point marken on the line T3-T4 is that point. (Note - the red point shudve been on the wire (T3-T4), it didnt come up in the image, sry abt that)
Okay, so at that point, the magnetic field is pointing in the direction of the blue arrow (consider it as a tangent to the circle)
The brown arro indicates the current.
If u arrange ur left hand in this form u will see the movement of the wire is towards the thick rigid wire as ur thumb points towards it.
im not sure abt this, astar plz check. thanks