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प्रश्न
Three waves A, B and C of frequencies 1600 kHz, 5 MHz and 60 MHz, respectively are to be transmitted from one place to another. Which of the following is the most appropriate mode of communication ______.
विकल्प
A is transmitted via space wave while B and C are transmitted via sky wave.
A is transmitted via ground wave, B via sky wave and C via space wave.
B and C are transmitted via ground wave while A is transmitted via sky wave.
B is transmitted via ground wave while A and C are transmitted via space wave.
उत्तर
Three waves A, B and C of frequencies 1600 kHz, 5 MHz and 60 MHz, respectively are to be transmitted from one place to another. Which of the following is the most appropriate mode of communication a is transmitted via ground wave, B via sky wave and C via space wave.
Explanation:
The radio waves emitted from a transmitter antenna can reach the receiver antenna by the following mode of operation.
- Ground wave propagation
- Sky wave propagation
- Space wave propagation
Mode of communication frequency range:
- Ground wave propagation – 500 kHz to 1710 kHz
- Sky wave propagation – 2 MHz to 40 MHz
- Space wave propagation – 54 MHz to 42 GHz
So, A is transmitted via ground wave, B via sky wave and C via space wave.
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