Magnetic field at the centre of the circle is, B=2Rμ0i
Magnetic field at the point on the axis is,
B2=2(R2+x2)23μ0iR2⇒B2=2(R2+(2R)2)23μ0iR2⇒B2=2(45)23Rμ0i=(52)3B
JEE Main 2022 — Physics Electromagnetism
The magnetic field at the centre of a circular coil of radius r, due to current I flowing through it, is B. The magnetic field at a point along the axis at a distance 2r from the centre is :
Held on 24 Jun 2022 · Verified 6 Jul 2026.
2B
2B
(52)3B
(32)3B
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