A long wire `AB` is placed on a table. Another wire `PQ` of mass `1.0 g` and length `50cm` is set to slide on two rails `PS` and `QR`. A current of `50 A` is passed through the wires. At what distance above `AB`, will the wire `PQ` be in equilibrium?
A. 25 mm
B. 50 mm
C. 75 mm
D. 100 mm
