Answer: E 0 /√n.
- A √(n) E<sub>0</sub> (slightly higher due to slower phase velocity)
- B E<sub>0</sub>/n
- C E<sub>0</sub> n
- D E<sub>0</sub>/√n
Correct answer: D. E<sub>0</sub>/√n
Explanation: In a dielectric: intensity I = ½nε_0 c E<sub>0</sub>². For same intensity: E<sub>medium</sub> = E<sub>vacuum</sub>/√n. The electric field amplitude decreases in a denser medium.
In an electromagnetic wave, the oscillating electric field (E) and magnetic field (B) are perpendicular to each other and to the direction the wave travels - a purely transverse wave that needs no medium, unlike sound.
Concept context
Maxwell's equations, EM spectrum, properties, and applications of each band.