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JEE Main202313 Apr 2023Evening ShiftPhysicsCommunication SystemActual

To radiate EM signal of wavelength λ with high efficiency, the antennas should have a minimum size equal to:

Options

  1. A2 λ
  2. Bλ 2
  3. Cλ 4
  4. Dλ

Correct answer

C. λ 4

Step-by-step solution

For efficient radiation and reception, the height of transmitting and receiving antennas should be comparable to a quarter of wavelength of the frequency used. So for efficient transmission of signals of wavelengths   λ the minimum length of antenna should be λ 4 .

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