Answer:
[tex]\phi_i = BA[/tex]
Explanation:
magnetic flux is the count of magnetic field lines passing through a given loop or area
As we know that magnetic flux is given by the formula
[tex]\phi = \vec B. \vec A[/tex]
here we also know that magnetic field B and plane of the coil is perpendicular in initial position
So the area vector is always perpendicular to the plane of the coil
so the angle between magnetic field and area vector is parallel to each other and this angle would be zero
so magnetic flux of the coil initially we have
[tex]\phi = BAcos0 = BA[/tex]