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प्रश्न
The frequency range of 3 MHz to 30 MHz is used for ____________.
विकल्प
Ground wave propagation
Space wave propagation
Sky wave propagation
Satellite communication
उत्तर
The frequency range of 3 MHz to 30 MHz is used for Sky wave propagation.
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संबंधित प्रश्न
Write a short note on surface wave propagation of electromagnetic waves.
State the factors which limit its range of propagation
In which directions do the electric and magnetic field vectors oscillate in an electromagnetic wave propagating along the x-axis?
Explain why ground wave communication mode cannot be used for long-distance communication using high frequencies
Describe briefly, by drawing suitable diagram, the sky wave ?
What is ground wave communication? On what factors does the maximum range of propagation in this mode depend?
In sky wave mode of propagation, why is the frequency range of transmitting signals restricted to less than 30 MHz?
The length of half wave dipole at 30MH2 is
Two waves A and B of frequencies 2 MHz and 3 MHz, respectively are beamed in the same direction for communication via sky wave. Which one of these is likely to travel longer distance in the ionosphere before suffering total internal reflection?
(i) The intensity of a light pulse travelling along a communication channel decreases exponentially with distance x according to the relation I = Ioe–αx, where Io is the intensity at x = 0 and α is the attenuation constant. Show that the intensity reduces by 75 per cent after a distance of `((In 4)/α)`
(ii) Attenuation of a signal can be expressed in decibel (dB) according to the relation dB = `10 log_10 (I/I_0)`. What is the attenuation in dB/km for an optical fibre in which the intensity falls by 50 per cent over a distance of 50 km?
