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For an antenna of length l, the emitted power varies as which of the following with respect to the wavelength λ?

1. l/λ
2. (l/λ)²
3. (l/λ)³
4. √(l/λ)

Correct answer: (l/λ)²

Solution

The emitted power from an antenna is proportional to the square of the ratio of its length to the wavelength, as this relationship accounts for the effective area and radiation pattern of the antenna, which increases with the square of the length-to-wavelength ratio.

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