Communications Question Bank

 13%

Page 1 of 8

1. The distance of coverage of  transmitting antenna is 12.8\,km. Then, the height of the antenna is

(Given that radius of earth =6400\,km)
A.
B.
C.
D.
E.
2. When radio waves passes through ionosphere, phase difference between space current  and capacitance displacement current is
A.
B.
C.
D.
3. A optical fibre  has a relative index of 0.8\%. What is the critical angle at the core-cladding interface.
A.
B.
C.
D.
4. Which one of the following statement is wrong ?
A.
B.
C.
D.
E.
5. If sky wave with a frequency of 50\,MHz is incident on D region at an angle of 30^{o}, then angle of refraction is
A.
B.
C.
D.
6. In frequency modulated wave
A.
B.
C.
D.
7. What happen inside optical fibre ?
A.
B.
C.
D.
8. In Statellite communication

1 . the frequency used  lies between 5\,MHz and 10\,MHz

2 . The uplink and downlink frequencies are different.

3 . The orbit of geostationary satellite lies in the equatorial plane at an inclination of 0^{o}.

In the above statements
A.
B.
C.
D.
E.
9. The velocity of a particle at which the kinetic energy is equal to its energy is
A.
B.
C.
D.
10. What should be the maximum acceptance angle at the air core interface of an optical fibre if n_{1} and n_{2} are the refractive indices of the core and the cladding, respectively
A.
B.
C.
D.