A regular polygon of 6 sides is formed by bending a wire of length 4 \(\pi\) meter. If an electric current of \(4 \pi \sqrt3 \) A is flowing through the sides of the polygon, the magnetic field at the centre of the polygon would be \(x × 10^{–7}\) T. The value of \(x\) is ____.
Correct Answer: 72
Solution and Explanation
The magnetic field at the centre of a regular polygon with \(n\) sides is given by:
\[ B = \frac{\mu_0 I n}{4\pi r} \left(\sin 30^\circ + \sin 30^\circ\right) \]
Substituting values:
\[ B = 72 \times 10^{-7} \, \text{T} \]
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