A long horizontal wire P carries a current of 50A. It is rigidly fixed. Another wire Q is placed…

A long horizontal wire P carries a current of 50A. It is rigidly fixed. Another wire Q is placed directly above and parallel to P, as shown in Figure 1 below. The weight per unit length of the wire Q is $0\cdot025\text{ N}\,\text{m}^{-1}$ and it carries a current of 25A. Find the distance ‘r’ of the wire Q from the wire P so that the wire Q remains at rest.