If the amplitude of an EM wave in vacuum is E 0 , in a medium of refractive index n (transparent), the E field amplitude:

√(n) E 0 (slightly higher due to slower phase velocity)

⚛️ Physics · Electromagnetic Waves · NEET & JEE

If the amplitude of an EM wave in vacuum is E₀, in a medium of refractive index n (transparent), the E field amplitude:

Answer: E₀/√n.

A √(n) E₀ (slightly higher due to slower phase velocity)
B E₀/n
C E₀ n
D E₀/√n

Correct answer: D. E₀/√n

Explanation: In a dielectric: intensity I = ½nε_0 c E₀². For same intensity: E_medium = E_vacuum/√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.

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If the amplitude of an EM wave in vacuum is E0, in a medium of refractive index n (transparent), the E field amplitude:

Concept context

More Electromagnetic Waves questions

If the amplitude of an EM wave in vacuum is E₀, in a medium of refractive index n (transparent), the E field amplitude: