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 P1: 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.