
Direction of magnetic field due to all six sides will be in the same direction, therefore we can write
B=6(4πrμ0I)(sin30∘+sin30∘), where r=distance of the sides from the centre.
=6(3π×3)10−7×4π3
=72×10−7T
Hence, x=72.
JEE Main 2024 — Physics Electromagnetism
A regular polygon of 6 sides is formed by bending a wire of length 4π meter. If an electric current of 4π3A is flowing through the sides of the polygon, the magnetic field at the centre of the polygon would be x×10−7T. The value of x is ______.
Held on 1 Feb 2024 · Verified 6 Jul 2026.
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