CBSE Class 12-science Answered

Here r₁ = 1 cm and r₂ =1  cm i.e., the distance of each wire from point P₁ and P₂ is same.

The net magnetic field at each point due to the two wires can be found out by using superposition principle.

At point P_1: Applying Right hand rule, magnetic B at point P₁ is directed perpendicular to the plane of the screen away from you due to both wires 1 and 2.                                              

Therefore magnetic field B due to each wire carrying equal current I,                      

Thus, since the magnetic field due to each wire is equal in magnitude and point in same direction, Therefore the net magnetic field at the point P₁ is 

where I = 2 A and r =1 cm = 0.01 m 

At point P₂: Applying Right hand thumb rule , magnetic field B at point P₁ is directed perpendicular to the plane of the screen away from you due to wire 1 but towards you due to wire 2 so the magnetic fields will subtract.

Now since distances of both wires from point P₂ is the same which is 1 cm and therefore the magnitude of magnetic field due to each wire at point P₂ is the same.

But since the magnetic field due to each wire points in opposite directions at point P₂, the net magnetic field is zero at P₂ using superposition principle.