Two identical wires A and B, each of length l, carry the same current I. Wire A is bent into a circle of radius R and wire B is bent to form a square of side a. If B_A and B_B are the values of magnetic field at the centres of the circle and square respectively, then the ratio (B_A)/(B_B) is

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(4) (π²)/(8√2). Circle: R=l/(2π), B_A=(μ₀ I)/(2R)=(πμ₀ I)/l. Square: a=l/4, B_B=4×(μ₀ I)/(4π(a/2))(2 sin 45°)=(2√2μ₀ I)/(π a)=(8√2μ₀ I)/(π l). (B_A)/(B_B)=(π²)/(8√2)

Two identical wires A and B, each of length l, carry the same current I. Wire A is bent into a circle of radius R and wire B is bent to form a square of side a. If B_A and B_B are the values of magnetic field at the centres of the circle and square respectively, then the ratio (B_A)/(B_B) is

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