Two coplanar

PHYSICS · Single correct · CBSE · Physics · Moving Charges and Magnetism · Moving Charges and Magnetism

Problem

Two coplanar, concentric circular loops have radii

R

and

2R

. The smaller loop carries a clockwise current of

5\,\text{A}

. What current must flow in the larger loop so that the net magnetic field at their common centre is zero? (a)

2.5\,\text{A}

anticlockwise (b)

20\,\text{A}

anticlockwise (c)

10\,\text{A}

anticlockwise (d)

10\,\text{A}

clockwise