Question:
(a) "EM wavelength correlates with the size of the radiating system." Give two examples.
(i) Why do long-distance radio broadcasts use shortwave bands?
(ii) Why are X-ray telescopes satellite-based, while optical/radio telescopes are ground-based?
(a) "EM wavelength correlates with the size of the radiating system." Give two examples.
(i) Why do long-distance radio broadcasts use shortwave bands?
(ii) Why are X-ray telescopes satellite-based, while optical/radio telescopes are ground-based?
(i) Why do long-distance radio broadcasts use shortwave bands?
(ii) Why are X-ray telescopes satellite-based, while optical/radio telescopes are ground-based?
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(a) Antenna size and atomic size. (b) Ionospheric reflection and atmospheric absorption.
Updated On: Feb 16, 2025
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Solution and Explanation
(a) 1. Radio transmitter antenna length ≈ radio wavelength. 2. Visible light wavelength ≈ size of emitting atoms/molecules. (b) (i) Shortwave bands reflect off the ionosphere, enabling long-distance propagation. (ii) X-rays are absorbed by the atmosphere; optical and radio waves are not.
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