For a single loop, radius
r1=2πL
BL=2r1μ0I=2Lμ0I×2π ...(1)
For a circular coil, radius
r2=2πNL
Bc=2r2μ0IN=2Lμ0IN2πN ...(2)
BCBL=N21 (from eqns (1) and (2))
JEE Main 2019 — Physics Electromagnetism
One of the two identical conducting wires of length L is bent in the form of a circular loop and the other one into a circular coil of N identical turns. If the same current is passed in both, the ratio of the magnetic field at the centre of the loop (BL) to that at the centre of the coil (BC), i.e. BCBL will be
Held on 9 Jan 2019 · Verified 6 Jul 2026.
N21
N1
N
N2
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