A long wire A carries a current of 10 amp. Another long wire B, which is parallel to A and separated by 0.1 m from A, carries a current of 5 amp. in the opposite direction to that in A. What is the magnitude and nature of the force experienced per unit length of B [μ0 = 4π x 10-7 weber/amp – m]
(a) Repulsive force of 10-4 N / m
(b) Attractive force of 10-4 N / m
(c) Repulsive force of 2π x 10-4 N / m
(d) Attractive force of 2π x 10-5 N / m