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For an electromagnetic wave moving in vacuum, the electric field is expressed as E = E₀ sin(kx − ωt). Which of the following quantities does not depend on the wavelength?

1. kω
2. k/ω
3. k²ω
4. ω

Correct answer: k/ω

Solution

The quantity k/ω represents the phase velocity of the wave, which is constant for a given medium and does not change with the wavelength. In contrast, the other options involve either k or ω directly, which are both dependent on the wavelength.

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