As magnetic field lines always form a closed loop, hence every magnetic field line creating magnetic flux in the inner region must be passing through the outer region. Since flux in two regions are in opposite direction.
∴ϕi=−ϕ0
JEE Main 2020 — Physics Electromagnetism
Consider a circular coil of wire carrying constant current I, forming a magnetic dipole. The magnetic flux through an infinite plane that contains the circular coil and excluding the circular coil area is given by ϕi The magnetic flux through the area of the circular coil area is given by ϕ0 . Which of the following option is correct?
Held on 7 Jan 2020 · Verified 6 Jul 2026.
ϕi=ϕ0
ϕi>ϕ0
ϕi<ϕ0
ϕi=−ϕ0
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