Two identical wires with a weight of 4.75E+4 N/m, are located one above the other, in a vertical plane above the surface of the earth. The wires are aligned north-south so that the earths's magnetic field will not affect them. Assume the distance of separation is 0.11 m and that they will carry the same current, but in opposite directions.
What must be the value of the current for the lower wire to levitate the upper wire?