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If electron density of the layer of ino...

If electron density of the layer of inosphere is ` 10 xx 10^(11)` and k is a constant , then critical frequency for reflection of radiowaves is

A

`k xx 10^(18) Hz `

B

` k xx 10^(12) Hz `

C

`k xx 10^(7) Hz `

D

` k xx 10^(6) Hz `

Text Solution

Verified by Experts

The correct Answer is:
D
By the relation ` , f_(c)=kN^(1//2)=k(10^(12))^(1//2)`
`= k xx 10^(6) Hz `
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MHTCET PREVIOUS YEAR PAPERS AND PRACTICE PAPERS-COMMUNICATION SYSTEM-Exercise 1
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  2. The ratio waves of frequency 300 MHz to 3000 MHz belong to

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  3. If electron density of the layer of inosphere is 10 xx 10^(11) and ...

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  4. If the critical frequency for sky wave propagation is 12 MHz , then th...

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  5. The sky wave propagation is suitable for radiowaves of frequency

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  6. A signal emitted by an antenna from a certain point can be received at...

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

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  8. Is it necessary for a transmitting antenna to be at the same height as...

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  9. When electromagnetic waves enter the ionised layer of ionosphere, then...

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  10. Name the type of waves which are used for line of sight (LOS) communic...

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  11. In space communcation , the information can be passed from on place ...

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  12. What fraction of the surface area of earth can be covered to estab...

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  13. Beyond which frequency, the ionosphere bends any incident electromagne...

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  14. For sky wave propagation of a 10 MHz signal, what should be the minimu...

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  15. In earth's atmosphere for F(1)-layer , the virutal height and critic...

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  16. Fading is the variation in the strength of a signal at a receiver due ...

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  17. In earth's atmosphere for E- layer , the virtual height and critical ...

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  18. If the TV telecast is to cover a radius of 120 km ( Given , the radiu...

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  19. Space wave propagation is used in (a) microwave communication (b) ...

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  20. Ozone layer above earth's atmosphere will not

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