Explore topic-wise MCQs in Electromagnetic Theory.

This section includes 58 Mcqs, each offering curated multiple-choice questions to sharpen your Electromagnetic Theory knowledge and support exam preparation. Choose a topic below to get started.

51.

In a waveguide, attenuation near the cut-off frequency is

A. low
B. high
C. very high
D. zero
Answer» E.
52.

Consider a standard rectangular and a circular waveguide having same dominant mode cut-off frequency, determine the ratio of area of circular waveguide to rectangular waveguide:

A. 1/π
B. 6.78/π
C. 0.69/π
D. π
Answer» C. 0.69/π
53.

A rectangular waveguide with air medium has dimensions a = 22.86 mm and b = 10.6 mm is fed by 3 GHz carrier from a coaxial cable, which of the following is a false statement for TE01 mode?

A. Propagating mode
B. Non-propagating mode
C. Propagating mode in case filled fully with dielectric material of proper dielectric constant
D. None of the above
Answer» B. Non-propagating mode
54.

In this mode, the electric field is purely transverse to the direction of propagation, whereas the magnetic field is not. Name the mode of propagation of microwaves.

A. Transverse Electromagnetic Waves
B. Transverse Electric Waves
C. Transverse Magnetic Waves
D. Hybrid Waves
Answer» C. Transverse Magnetic Waves
55.

An optical fibre cable consists of three parts. One of these is a protective outercoating of the cable. Select that protective outer coating from the given options.

A. Fibre
B. Buffer coating
C. Cladding
D. Core
Answer» C. Cladding
56.

A typical optical fiber has

A. high refractive index core & low refractive index cladding
B. Low refractive index core & high refractive index cladding
C. Uniform refractive index core surrounded by variable refractive index cladding
D. None of the above
Answer» B. Low refractive index core & high refractive index cladding
57.

In a single-mode fiber, the power received is 1% that of the transmitted power. The attenuation of a single-mode fiber is of the order of

A. 50 dBm
B. -20 dBm
C. 030 dBm
D. -2 dBm
Answer» B. -20 dBm
58.

Microwave energies propagate the length of the waveguide by ____ its sidewalls.

A. Moving off
B. Refraction
C. Reflection off
D. None of these
Answer» D. None of these