The two linear parallel conductors carrying currents in the opposite direction…………………each other.

Two long straight parallel conductors carrying currents in the opposite directions

Two linear parallel conductors carrying currents in the same direction attract each other and two linear parallel conductors carrying currents in opposite direction repel each other. The force acting per unit length due to currents I_1 and I_2 in two linear parallel conductors held distance r apart in vacuum in SI unit is F=(mu_0)/(4pi)(2I_1I_2)/(r) Read the above passage and answer the following questions: (i) What is the basic reason for the force between two linear parallel conductors carrying currents? (ii) Two straight wires A and B of lengths 2cm and 20cm , carrying currents 2*0A and 5*0A respectively in opposite directions are lying parallel to each other 4*0cm apart. The wire A is held near the middle of wire B. What is the force on 20cm long wire B? (iii) What does this study imply in day to day life?