120. Geosynchronous communication satellites travel around the Earth in circular orbits with a forward speed of about lun/h.
A.11,200
B.0
C.36,000
D.22,800

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121. The lifetime of a geosynchronous communication satellite is about years
A.5
B.10
C.20
D.50

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122. Most of the communication satellites are stationed to the West of their service are as in order to reduce their
A. eclipse period
B. loss of power
C. battery power provision
D. mass of station-keeping fuel

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123. Space communication links are being increasingly moved into Ka-band (20-30 GHz) because it
A. offers a much wider available bandwidth
B. does not suffer from atmospheirc attenuation
C. permits the use of smaller antenna
D. does not suffer from rain attenuation

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124. A geosynchronous satellite
A. has the same period as that of the Earth
B. has a circular orbit
C. rotates in the equatorial plane
D. has all the above

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125. The INTELSAT-IV satellite launched in 1974 had two earth-coverage antennas and two narrower-angle antennas subtending 4?50. The signal from narrow-angle antenna was stronger than that from earth-coverage antenna by a factor of
A. 17.34/4.5
B. 17.34 x 4.5
C. (17.34/4.5)2
D. (17.34/4.5)4

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126. The number of days when Earth's shadow falls on a geosynchronous satellite is
A.88
B.277
C.5
D.10

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