Concept:Electromagnetic waves are transverse waves where the electric field vector \(\vec{E}\), magnetic field vector \(\vec{B}\), and wave velocity vector \(\vec{v}\) are mutually perpendicular.
Formula / Reaction:$$\vec{E} \cdot \vec{B} = 0 \implies \theta = 90^\circ$$
Solution:- The electric field, magnetic field, and direction of propagation form a right-handed orthogonal coordinate system: \(\vec{S} = \frac{1}{\mu_0} (\vec{E} \times \vec{B})\).
- Thus, the angle between \(\vec{E}\) and \(\vec{B}\) is always \(90^\circ\) (\(\pi/2\text{ rad}\)).
Why other options are incorrect:- Opt_B: Parallel vectors (\(0^\circ\)) cannot sustain electromagnetic wave propagation.
- Opt_C: An angle of \(45^\circ\) is non-orthogonal and physically invalid for plane EM waves in free space.
- Opt_D: Anti-parallel vectors (\(180^\circ\)) have a cross product of zero and cannot transport wave energy.
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