Hint: The magnetic field lines formed around a current carrying loop are circular in shape. So, think about the magnetic flux generated inside and outside the loop and then compare.
Complete step-by-step answer:
Magnetic Flux-It is defined as the number of magnetic field lines that pass through a given closed surface. It is a measure of the magnetic field intensity from a given area.
It is the product of the magnetic field and the projected surface area through the field.
The formula for magnetic flux is:
ϕ=B⋅A=BA‌cos‌θ Magnetic flux follows superposition, as flux due to different fields is added to calculate the net flux through a given area.
Flux is a vector, so sign is concerned with it, to mention its direction. It describes the effects of the magnetic force onsomething occupying a given area.
Applications of magnetic flux
1) In electric motors and generators, where faraday's laws are used to generate the fields.
Used in explaining the non-existence of magnetic monopoles.
Here,
Ï•i and
Ï•0 are the fluxes through the inner and outer regions of the loop. In case of a current carrying loop, circular magnetic field lines are generated. Now taking the vector inside and outside the loop, they are exactly the same
in magnitudes but opposite in directions.
So, the outer and inner fluxes are the same.
φi=φ0 But are just opposite in direction
φi=−φ0 The correct option is (A).
Note: One should be thorough with the concept of magnetic flux and the area considered. Despite the outer regionhaving a larger area, the magnetic fields link only with the small projected area.