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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
If the earth did not have atmosphere, would its average surface temperature be higher or lower than what it is now? Explain.
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(b) the intensity is higher
(c) the frequency is higher
(d) the photon energy is higher.
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| Cell containing vacancy | K | L | M |
| Energy in keV | 69.5 | 11.3 | 2.3 |
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Name the electromagnetic radiation that has been used in obtaining the image below.
