Two identical circular loops of radius are placed coaxially

PHYSICS · Single correct · CBSE · Physics · Magnetic Effects of Electric Current · Magnetic Effects of Electric Current

Problem

Two identical circular loops of radius

5\,\text{cm}

are placed coaxially. One loop has 30 turns, the other 20 turns. Each carries a current of

4\,\text{A}

, but in opposite directions. What is the magnitude and direction of the net magnetic field at their common centre? (a)

2.5\times10^{3}\,\mu\text{T}

, along the field of the 30-turn loop (b)

1.0\times10^{3}\,\mu\text{T}

, along the field of the 30-turn loop (c)

5.0\times10^{2}\,\mu\text{T}

, along the field of the 30-turn loop (d)

5.0\times10^{2}\,\mu\text{T}

, opposite to the field of the 30-turn loop