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The highest frequency of transmitted wav...

The highest frequency of transmitted wave that is returned to the earth by layer of ionosphere after having been sent straight (normally) to it, is called

A

maximum usable frequency

B

critical frequency

C

launching frequency

D

threshold frequency

Text Solution

Verified by Experts

The correct Answer is:
B
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AAKASH SERIES-COMMUNICATION SYSTEMS -Exercise - IA (Sky Wave propagation)
  1. When a sky wave is reflected on to the ground

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  2. The height of F(2) layer is (1) 240 km to 400 km in day time (2) 3...

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  3. The main role of F(2) layer in communication is

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  4. Sky wave have a wavelength

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  5. Transmission via sky waves is impossible for the frequencies

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  6. The layer responsible for reflection of ratio wave is

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  7. Read the following (1) Refractive index can be less than one (2) M...

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  8. With increases of ionic density, the R.I, of ionosphere

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  9. The highest frequency of transmitted wave that is returned to the eart...

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  10. The highest frequency of transmitted wave that is returned to the eart...

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  11. The expression for critical frequency is

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  12. Two waves A & B of frequencies 2 MHz & 3 MHz & 3 MHz respectively are ...

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  13. E.M. waves with frequencies greater than critical frequency of ionosph...

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  14. Skip zone in radio wave transmission is that range where

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  15. The F-layer persists in earth's atmosphere at night because

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  16. If sky wave with a frequency of 60 MHz is incident on D-region at angl...

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  17. If a radio-receiver amplifies all the signal frequencies equally well,...

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  18. Refractive index of ionosphere is

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  19. Three waves A, B and C of frequencies 1600 kHz, 5 MHz and 60 MHz, resp...

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  20. Which of the following frequencies will be suitable for beyond the hor...

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