239. With reference to Q-59, if (a) is the semi-major axis of elliptical transfer orbit and (r) is the distance of a given point on the orbit from the centre of earth, ther the orbital velocity of the satellite at that point is given by (IL = GM)
A. u = 1(21t- ?a)
B. u =?r a
C. u2 = (-Lir ?)
D. u =a
240. The orbital velocity at the apogee point in an eccentric elliptical orbit increases when the elliptical orbit is transformed into a circular orbit with apogee point remaining the same. This increment in velocity is the minimum when
A. elliptical orbit plane is indined at 45? to the circular orbit plane
B. elliptical orbit plane is at right angles to the circular orbit plane
C. elliptical orbit and circular orbit are in the same plane
D. none of these
241. Molniya orbit serves the purpose of a geosynchronous orbit for high latitude regions. The number of satellites usually required at different phases of the same Molniya orbit to provide uniterrupted service to a given area is
A.3
B.6
C.1
D.4
242. For satellite communication, the frequency should be the critical frequency of ionosphere.
A. equal to
B. less than
C. come than
D. none of the above
243. Before transmitting to the satellite, the wide-band satellite signal is apmplified bY
A. waveguide
B. klystron
C. travelling wave tube
D. any of the above
244. A satellite repeater serves which of the following purposes?
A. It receivers signal from the satellite
B. It repeats the satellite signals many times
C. It translates the signal to new frequency band
D. None of the above
245. The telephone channels in a communication satellite are assembled in
A. FM
B. AM
C. TDM
D.FDM
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