Criado por James Middleton4075
mais de 9 anos atrás
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What type of waves are used to communicate with satellites in a low polar orbit and what type are used for waves with a high geostationary orbit?
Describe two features of a radio wave
Radio waves with a frequency below what MHz are reflected by the ionosphere?
Radio waves with a frequency above what GHz are reduced in strength because they are absorbed and scattered by rain, dust and other effects in the atmosphere?
Radio waves between what frequencies can pass through the Earth's atmosphere/
What type of signals are used in satellite communication and why?
What other type of waves are used to transmit information to satellites?
Why does the dish used in satellite communication have to be many times larger than the wavelength when using microwaves?
How is diffraction useful?
What are the types of diffraction and what they look like?
The amount that a wave is diffracted by depends on the size of the gap and the wavelength of the wave. What do large gaps do and when does maximum diffraction happen?