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The critcal frequency for sky wave propa...

The critcal frequency for sky wave propagation if maximum number density of electrons in ionosphere is `10^(10) m_(-3)` is

A

300 kHz

B

600 kHz

C

900 kHz

D

1 MHz

Text Solution

Verified by Experts

The correct Answer is:
C
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Knowledge Check

  • The critcal frequency for sky wave propagation if maximum number density of electrons in ionosphere is 10^(3) m_(-3) is

    A
    300 kHz
    B
    600 kHz
    C
    900 kHz
    D
    1 MHz

  • For sky wave propagation of 10 MHz signal, what should be minimum electron density in ionsopher ? [g = 9 m//s^(2)]

    A
    `1 2 xx 10^(12) m^(-3)`
    B
    `10^(6)m^(-3)`
    C
    `10^(14)m^(-3)`
    D
    `10^(22)m^(-3)`

  • Assertion : Electromagentic waves with frequencies more than the cirtical frequency of ionosphere cannot be used for communication using sky wave propagation. Reason : The refractive index of the ionosphere becomes very high for frequencies higher than the critical frequency .

    A
    Assertion is True . Reason is True, Reason is a correct explanation for Assertion
    B
    Assertion is True , Reason is True, Reason is not a correct explanation for Assertion
    C
    Assertion is True, Reason is Fase.
    D
    Assertion is False but, Reason is True .

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