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प्रश्न
Give a reason for the following:
It is necessary to use satellites for long-distance TV transmission. Why?
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उत्तर
- It is necessary to use satellites for long-distance TV transmissions because television signals are of high frequencies and high energies. Thus, these signals are not reflected by the ionosphere.
- Hence, satellites are helpful in reflecting TV signals. Also, they help in long-distance TV transmissions.
संबंधित प्रश्न
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| Cell containing vacancy | K | L | M |
| Energy in keV | 69.5 | 11.3 | 2.3 |
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Answer briefly.
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Name one radiation having the wavelength longer than the wavelength of these radiations.
Name the electromagnetic radiation that has been used in obtaining the image below.
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