A long wire A carries a current of 10 A. Another long wire B, which is parallel to A and separated by 0.1 m from A, carries a current of 5 A, in the opposite direction to that in A. What is the magnitude and nature of the force experienced per unit length of B?
$({\mu }_0=4\mathrm{\pi }\times {10}^{-7}weber/amp-\mathrm{m})$
 

What will happen if two thin, long parallel wires separated by a distance "d" carry current "i" in the same direction?

A rectangular loop carrying a current \(\mathrm{I_1}\), is situated near a long straight wire carrying a steady current \(\mathrm{I_2}\). If the wire is parallel to one of the sides of the loop and is in the plane of the loop as shown in the figure, then the current loop will:
         

As indicated, a long, straight conductor XY carrying a current i₁ is placed antiparallel to a conductor AB of length l carrying a current i₂. How much of a force is acting on AB?

1. ${\mu }_0{i}_1{i}_2$

2.  $\frac{{\mu }_0{i}_1{i}_2}{\mathrm{\pi }}$

3. $\frac{{\mu }_0{i}_1{i}_2}{2\mathrm{\pi }}$

4. $2{\mu }_0{i}_1{i}_2$