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During the propagation of electromagnetic waves in a medium:

1. Electric energy density is double of the magnetic energy density.
2. Electric energy density is half of the magnetic energy density.
3. Electric energy density is equal to the magnetic energy density.
4. Both electric and magnetic energy densities are zero.

Correct answer: Electric energy density is equal to the magnetic energy density.

Solution

In electromagnetic waves, the electric and magnetic fields are interrelated and propagate together, leading to equal energy densities for both components in a vacuum or uniform medium.

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