Concept:Magnetic flux measures the number of magnetic field lines passing perpendicularly through a surface. It is mathematically the dot product of the magnetic field vector and the area vector (which is normal to the surface).
Formula:$$ \Phi = \mathbf{B} \cdot \mathbf{A} = BA \cos(\theta) $$
Solution:- The flux is maximized when the mathematical function \( \cos(\theta) \) reaches its maximum positive value.
- The maximum value of \( \cos(\theta) \) is 1, which occurs exactly at \( \theta = 0^\circ \).
- At this angle, the magnetic field is perfectly parallel to the area vector (meaning the field is hitting the surface perfectly face-on).
Why other options are incorrect:Option B (\( 90^\circ \)) yields zero flux. Option C (\( 180^\circ \)) gives the maximum negative flux. Option D (\( 45^\circ \)) yields an intermediate value.
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