10 Question-Answer on space communication
1. In space communication, the sound wave can be sent from one place to another
(a) Through space
(b) Through wires
(c) By superimposing it on undamped electromagnetic waves
(d) By superimposing it on damped electromagnetic waves
Ans: (c)
2. In space communication, the information can be passed from one place to another at a distance of 100 km in
(a) 1 sec
(b) 0.5 sec
(c) 0.003 s
(d) None of above
Ans: ( d)
3. The ground wave propagation is suitable for radio waves of frequency
(a) Upto 2 MHz
(b) From 2 MHz to 20 MHz
(c) From 2 MHz to 30 MHz
(d) None of above
Ans: (a)
4. The electromagnetic waves of frequency range 100 to 300 GHz are used in
(a) Sky wave propagation
(b) T.V. communication
(c) Microwave communication
(d) Ground wave communication
Ans: (c)
5. The space wave propagation is utilized in
(a) Only television communication
(b) Only radar communication
(c) Only microwave communication
(d) All of them
Ans: (d)
6. Fading is the variation in the strength of a signal as a receiver due to
(a) Interference of waves
(b) Diffraction of waves
(c) Polarization of waves
(d) None of the above
Ans: (a)
7. Space wave propagation is
(a) Tropospherical propagation
(b) Sky wave propagation
(c) Line of sight propagation
(d) None of the above
Ans: (a,c)
8. Which of the following is better propagation mode to propagate television frequency modulation and radar signals
(a) Satellite communication
(b) Ground propagation
(c) Polarized communication
(d) None of the above
Ans: ( a)
9. The wavelength of an electromagnetic wave on a wave guide
(a) Is directly proportional to the group velocity
(b) Is inversely proportional to the phase velocity
(c) Is less than in free space
(d) Is greater than in free space
Ans: ( d)
10. In ultra high frequency range the frequencies are propagated by means of
(a) Surface waves
(b) Sky waves
(c) Space waves
(d) Ground waves
Ans: (c)