COMEDK Exam 2019 Solved Paper

Magnetic field at any point due to a straight current carrying wire is given byB=‌

µ0I

2πd

where, d is the distance of the point from the wire and I1 is current flowing in the wire.
Force due to this magnetic field on current carrying wire is given by
F=BIL
where, L is the length of the wire.
∴ Force on wire B due to wire A,FA=BIL
⇒‌‌FA=‌

µ0×1

2πd

×2×L
Force on wire B due to wire C,FC=BIL
⇒‌‌FC=‌

µ0×3

2πd

×2×L
It is clear that FC>FA. Hence, net force is towards wire C.