# Parallel Plate Waveguide MCQ’s

This set of RF & Microwave Circuit Design Multiple Choice Questions & Answers (MCQs) focuses on “Parallel Plate Waveguide”.

1. The fringe effect can be neglected in a parallel plate waveguide is because of:
a) The dielectric material used
b) Width of the plates is greater than the distance between the plates
c) Material of the parallel plate waveguide used
d) None of the mentioned

2. The characteristic impedance of a parallel plate waveguide is given by:
a) η*D/W
b) η*W/D
c) D/ η*W
d) η*√(D/W)

3. The modes of wave propagation that a parallel plate waveguide can support are:
a) TEM, TE, TM modes
b) TM, TE modes
c) TEM, TM modes
d) TEM, TE modes

4. If the width of a parallel plate waveguide is 30 mm and the distance between the parallel pates is 5 mm, with an intrinsic impedance of 377Ω, then the characteristic impedance of the wave is:
a) 50 Ω
b) 62.833 Ω
c) 100 Ω
d) None of the mentioned

5. The wave impedance of a TM mode in a parallel plate waveguide is a:
a) Function of frequency
b) Independent of frequency
c) Proportional to square of frequency
d) Inversely proportional to square of frequency

6. For TM2 mode, if the distance between two parallel plates of a waveguide are 40 mm, then the cut off wavelength for TM2 mode is:
a) 20 mm
b) 80 mm
c) 40 mm
d) 60 mm

7. In TM mode, if the direction of wave propagation is in ‘z’ direction, then:
a) HZ=0
b) EZ=0
c) EY=0
d) HY=0

8. In a parallel plate waveguide, for a propagating mode, the value of β is:
a) Real
b) Complex
c) Imaginary
d) Cannot be defined

9. For a parallel waveguide, the dominant mode for TM propagation is:
a) TM0 mode
b) TM1 mode
c) TM2 mode
d) Dominant mode does not exist

10. For a parallel plate waveguide, which of the following is true?
a) No real power flow occurs in the ‘z’ direction
b) Power flow occurs in ‘z’ direction
c) No power flow occurs in any direction
d) Wave propagation in z direction is not possible in any mode

11. If in a parallel plate waveguide, PL=4 mW/m and Pₒ=10 mW/m, then what is the conduction loss?
a) 0.5
b) 0.4
c) 0.1
d) 0.2

12. Phase velocity of the plane waves in the two direction in a parallel plate waveguide is:
a) 1/√(μ∈)secant θ
b) 1/√(μ∈)cosecant θ
c) 1/√(μ∈)tangent θ
d) 1/√(μ∈)cosine θ

13. TE mode is characterized by:
a) EZ=0
b) HZ=0
c) Ex=0
d) Ey=0

14. If the distance between the two plates of a parallel plate waveguide is 20 mm and is operating in TE₂ mode, then the cut off frequency of TE₂ mode is:
a) 20 MHz
b) 15 GHz
c) 5 GHz
d) None of the mentioned

15. The wave impedance for a non-propagating mode in TE mode is:
a) K/β
b) Imaginary
c) Zero
d) Non-existing