As shown in the figure, a current of 2 A flows in an equilateral triangle of side 4√3 cm. The magnetic field at the centroid O of the triangle is: [Neglect Earth’s magnetic field.] Image
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As shown in the figure, a current of 2 A flows in an equilateral triangle of side 4√3 cm. The magnetic field at the centroid O of the triangle is: [Neglect Earth’s magnetic field.] Image

G1 Physics · Accepted Answer

Distance of centroid from each side is d = (side/2)tan30° = 2 cm. Field due to one side is μ₀I/(2πd) sin60°. Three sides contribute in the same direction, giving B = 3√3 × 10⁻⁵ T.