Electronics and Communication Engineering - Electromagnetic Field Theory MCQs Part 5

1.Which one is correct option?

A. TEM mode exist in free space of infinite boundary
B. TEM mode exist in two conductor pattern system for finite-boundary
C. TEM mode exist in waveguide only
D. Both (a) and (b)

 Answer Option D

2.A vertical loop antenna, like a horizontal dipole, is vertically polarised.

A. True
B. False

 Answer Option B

3.The attenuation in a waveguide near the cut off frequency is

A. zero
B. low
C. high
D. very high

 Answer Option A

4.The electric flux and field intensity inside a conducting sphere is

A. minimum
B. maximum
C. uniform
D. zero

 Answer Option D

5.T.V. antennas are usually

A. Yagi-Uda
B. loops
C. helical
D. parabolic

 Answer Option A

6.Measurement of radiation resistance by reflection method is suitable for

A. parasitic element antennas
B. low frequency vertical conductor antenna
C. all type of antennas
D. none of the above

 Answer Option A

7.A lossless transmission line is connected to two identical voltage source as shown in figure. The impedance measured at the midpoint AA' is

A. ∞
B. 100
C. 50
D. 25

 Answer Option A

8.A loss less transmission line is terminated in a load which reflects a part of the incident power. The measured VSWR is 2. The percentage of the power that is reflected back is

A. 57.73
B. 33.33
C. 0.11
D. 11.11

 Answer Option D

9.A higher directivity is specified by

A. high gain low BW (Beamwidth)
B. high gain high BW
C. low gain high BW
D. none of the above

 Answer Option A

10.The best excited reflector from a wave guide is

A. horn
B. parabolic
C. biconical
D. corner

 Answer Option A

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