Electronics and Communication Engineering - Electromagnetic Field Theory MCQs Part 8

1.Two LOS antennas having power gains of G1 and G2 are separated transmitted power, Pr is received power turn Pr/Pt will be proportional to

A.
B.
C.
D.

 Answer Option A

2.∇2 is

A. vector
B. scalar
C. depend on direction
D. none

 Answer Option B

3.End fire array has narrow bandwidth.

A. True
B. False

 Answer Option A

4.Which of the following antenna is best guided by a waveguide?

A. Biconical
B. Horn
C. Helical
D. Dish

 Answer Option B

5.Poynting vector is the rate of energy flow having

A. W/m2
B. W-m
C. kWh/s
D. W/m

 Answer Option A

6.Refraction of electromagnetic waves occurs when they

A. pass through a small slot in a conducting plane
B. pass into a medium of different dielectric constant
C. are polarized at right angles to the direction of propagation
D. encounter a perfectly conduction surface

 Answer Option A

7.The impedance inversion may be objected with

A. a short-circuited stub
B. an open-circuited stub
C. a half-wave line
D. a quarter-wave line

 Answer Option D

8.The force acting on a charge q moving with velocity in a region of electric field and magnetic field is

A. r + x
B. q( + x )
C. q( + x )
D. q

 Answer Option C

9.An electromagnetic wave incidents on a perfect insulator at an angle. If the wave is not entirely parallel polarized, then

A. the reflected wave will be entirely polarized parallel to the plane of incidence
B. there will be no reflection
C. the reflected wave will be entirely polarized perpendicular to the plane of incidence
D. any of the above

 Answer Option C

10.Coaxial cables can be used for which frequency?

A. 15 kHz
B. 10 MHz
C. 200 MHz
D. 2000 MHz

 Answer Option C

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