Concept:Magnetic flux measures the total magnetic field passing directly through a given surface area. Maximum flux occurs when the field passes perpendicular to the surface (which means parallel to the area's normal vector).
Formula:$$ \Phi = BA \cos(\theta) $$
Solution:- The variable \( \theta \) is the angle between the magnetic field vector and the vector area (normal vector).
- The mathematical function \( \cos(\theta) \) dictates the magnitude. It hits its maximum positive value of 1 when \( \theta = 0^\circ \).
- Therefore, flux is maximized at \( 0^\circ \).
Why other options are incorrect:Option B yields exactly zero flux (lines scrape the surface). Option C gives the maximum negative value (depending on sign convention, but 0 is standard for max positive). Option D gives a partial flux value.
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