A straight segment `OC`(of length L meter) of a circuit carrying a current `I amp` is placed along the x- axis ( fig.). Two infinetely long straight wires ` A and B` , each extending from ` z = -oo to +oo`, are fixed at y = -a meter and y = +a meter respectively, as shown in the figure.
If the wires ` A and B` each carry a current `I amp` into the plane of the paper, obtain the expression for the force acting on the segment ` OC`. What will be the force on `OC` if the current in the wire `B` is reversed?

Options

A. `((mu_(0)I^(2))/(pi)) 1n ((L^(2)+a^(2))/(a^(2)))(-hat(k))`
B. `((mu_(0)I^(2))/(2pi)) 1n ((L^(2)+a^(2))/(a^(2)))(-hat(k))`
C. zero
D. None of these

Answer

D