MCQ on Guided Waves

MCQ on Guided Waves

MCQ on Guided Waves, Electromagnetic MCQ, Guided wave in Electromagnetic field MCQ, Guided wave in EM Field MCQ, MCQ on Guided Wave in EM Field, Waveguide Question Answers, Waveguide MCQ.

Objective Type Questions

1. When a wave is propagating in x-direction, TE wave has E_x equal to

• zero
• E_y
• E_z
• E_y + E_z

Answer: zero

2. For a wave propagating in z-direction in a hollow rectangular waveguide, TEM wave has

• E_z = o
• H_z = o
• all components of E and H are zero
• E_x = o, H_z = o

Answer: all components of E and H are zero

3. The cut-off frequency of TEM wave is

• zero
• f
• infinity
• that of TE₁₀

Answer: zero

4. If a = 2 cm, b = 1 cm for a waveguide, the cut-off frequency for TE₁₀ mode is

• 0.75 GHz
• 7.5 GHz
• 1.5 GHz
• 1.5 MHz

Answer: 7.5 GHz

5. If the cut-off frequency for the dominant mode in a rectangular waveguide is 4 GHz, the dimension of the broad wall along x-axis is

• 4 cm
• 3.75 cm
• 5 cm
• 37.5 cm

Answer: 3.75 cm

6. If f =10 GHz, the broad dimension of a rectangular waveguide, a = 2 cm, the cut-off frequency for TE₁₀ is

• 0.75 GHz
• 7.5 GHz
• 10 GHz
• 5 GHz

Answer: 7.5 GHz

7. At f = 10 GHz, a = 2 cm, b = 1 cm, the cut-off frequency for TE₀₁ is

• 10 GHz
• 1.5 GHz
• 15 GHz
• 7.5 GHz

Answer: 15 GHz

8. If in a rectangular waveguide the attenuation constant is 2 dB/m and the phase constant is 2 rad/m, the propagation constant is

• 2 + j2 dB/m
• 2 + j2 np/m
• 2 dB/m
• 2 np/m

Answer: 2 + j2 dB/m

9. If β = 3oo rad/m for TE₂₁ mode in a rectangular waveguide, the guide wavelength for TE₂₁ is

• 0.209 cm
• 0.209 m
• 2.09 m
• 20.9 cm

Answer: 0.209 m

10. The cut-off frequency for TE₁₀ is 5 GHz at an operating frequency of 6 GHz. The phase constant for TE₁₀ is

• 69.5 rad/m
• 6.95 rad/m
• 0.833 rad/m
• 1.2 rad/m

Answer: 69.5 rad/m

11. If the resonant frequency is 6 GHz, the time averaged stored energy is 10 Joules and the power dissipation is 20 watts in a resonator, the quality factor is

• 188.49
• 188.49 × 10⁹
• 200
• 188

Answer: 188.49 × 10⁹

12. The ideal value of quality factor is

• ∞
• 0
• 100
• very small

Answer: ∞

13. If \eta _{TM}^{mn}=100, \eta _{TE}^{mn}=150, the intrinsic impedance is

• 122.47Ω
• 1.5Ω
• 0.333Ω
• 12.247Ω

Answer: 122.47Ω

14. If the phase constant of TM₂₁ is 320rad/m, α = 0 at an operating frequency of 10 GHz, the characteristic impedance of TM₂₁ is

• 32Ω
• 539Ω
• 300Ω
• 53.9Ω

Answer: 539Ω

15. The cut-off wavelength for the dominant mode in a rectangular waveguide having dimensions 4 × 3 cm is

• 12 cm
• 8 cm
• 1.33 cm
• 0.75 cm

Answer: 8 cm

16. The cut-off wavelength for TE₃₂ in a waveguide is 10 GHz. The guide wavelength for TE₃₂ mode is

• 3 cm
• 3.2 cm
• 6 cm
• 3 m

Answer: 3 cm

17. Skin depth in the copper wall of a waveguide operating at f = 6.25 GHz is

• 8.39 mm
• 83.9 mμ
• 83.9 mm
• 839 mm

Answer: 83.9 mμ

18. The mode of propagation in an air-filled waveguide of 2 × 1 cm dimensions operating at 10 GHz is

• TE₀₁
• TE₂₁
• TE₁₀
• TE₁₁

Answer: TE₁₀

19. If the propagation constant in a waveguide is 105+ j10, np/m the attenuation constant is

• 105 np/m
• 105 dB/m
• 10.5 np/m
• 115 np/m

Answer: 105 np/m

20. If γ_mn = α_mn, in a waveguide

• propagation takes place
• no propagation takes place
• energy is increased
• energy is decreased

Answer: no propagation takes place