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The magnitude of the magnetic field at the centre of an equilateral triangular loop of side 1 m which is carrying a current of 10 A is : [Take μ 0 = 4 π × 10 –7 NA –2 ]

1. 3 μ T
2. 18 μ T
3. 9 μ T
4. 1 μ T

Correct answer: 18 μ T

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