Q.

Two long parallel wires X and Y, separated by a distance of 6 cm, carry currents of 5 A and 4 A, respectively, in opposite directions as shown in the figure. Magnitude of the resultant magnetic field at point P at a distance of 4 cm from wire Y is x×10–5 T. The value of x is _____. Take permeability of free space as μ0=4π×10–7 SI units.          [2025]


Ans.

(1)

At P

B→=B→1+B→2=μ0i22πr2k^–μ0i12πr1k^

B→=μ02π(44×102–510×102)k^

     =1×10–5 T

⇒ x=1