Here are the Freee Objective Questions On Ms Excel
Objective Question Bank
Unit 1
UNIT -1 OBJECTIVE QUESTIONS Choose the corr ect altern al ternati ative ve..
1. The range of microwave frequencies is given by a) 1 GHz to 300 GHz b) 1 MHz to 300 MHz c) 1 KHz to 300 kHz d) None
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2. In which of the following application does microwaves a) Tele communications b) RADARs c) Radio Astronomy d) All the above
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3. Which of the following are advantages of microwaves a) High directivity b) High bandwidth c) Reliabilty d) All the above
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4. As the frequency increases the beam width and directivity a) Decreases, decreases b) Decreases , increases c) Increases, decreases d) Increases, increases
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5. The velocity of light C interms of permiablity µ 0, є0in space is given by a) c = √ (µ0/ є0) b) c = √ (є0/ µ0) c) c = √ (µ0* є0) d) None
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7. For a dominent dominent mode the value of cut – off wave length is a) Zero b) Minimum c) Maximum d) None
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8. which of the following is the dominent dominent mode in TM mn wave guide a) TM12 b) TM21 c) TM11 d) TM22
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9. The rate at which the wave changes its phase is called a) Phase velocity b) Group velocity c) Particle velaocity d) None
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10. The constant β interms of guide wave length λ g is a) β = 2π/ λ g b) β = λg/2π c) β = 2π/ λ g2
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6. Which of the following gives the cut – off off frequency f c , where c= velocity of light, m,n = mode numbers, a,b= dimensions of waveguide a)f c =c/2 * √ (m/a)2 + (n/b)2 b) f c =c/2 * √ ( m/a)2 - (n/b)2 c) f c =c/2 * √ (m/a)2* (n/b)2 d) None
11. The phase velocity Vp is given by which of the following a) V p = β/ω b) V p = ω/ β c) V p = β/ω2
ECE Dept, Sreyas Institute of Engineering & Technology
d) β = λg2/2π
d) None
Microwave Engineering
Objective Question Bank
Unit 1
12. What is the value of cut – off wave length for the dominent waves a)λ c11 = 2ab/√(a2-b2) b) λ c11 = 2ab/√(a2+b2) c) λ c11 = √(a2-b2)/ 2ab d) none
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13. The Wavelength correspond to Microwave frequency range is 3-30 GHz is a) 100-10 cm b) 10-1cm c) 1-0.1 cm d) 0.1-0.001cm
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14.The main advantage of microwave is thata) Highly Directive. b) Moves at the speed of light. c) S/N ratio grater. d) High penetration power.
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15. In a rectangular waveguide, which of the following modes are known as the degenerate modes [ a) TE and TE b) TE and TM 01
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c) TM and TM 01
10
11
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d) TE and TM 01
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16. The electric and magnetic fields inside the waveguide can be determined by solving from ______________ equations subject to the appropriate boundary conditions [ a)Thevenin’s b) Norton’s c) Faraday’s d) Maxwell’s 17. Generally Waveguides are not preferred below the frequencies of a) 1 GHz b) 25GHz c) 50 GHz
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[ ] d) 100 GHz
18. ________ is defined as the rate at which the wave propagates through the waveguide [ ] a) Phase Velocity b) Group Velocity c) Guide Velocity d) Wave Velocity 19. The frequency bands above 1 GHz are referred to as __________frequency bands a) Milliwave b) Low c) Microwave d) Very low
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20. A joint discontinuity in a wave guide a) Independent of frequency c) increases at higher frequency
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21. A Piston attenuation is a)Flap attenuator c)Vane attenuator
b) increases at low frequency d) decreases at higher frequency
b)Waveguide below cutoff d)Mode filter
22. Which one of the following modes does not exist in waveguides a)TE b)TM c)TEM
d)None
23. For handling large microwave power, the best medium is a) Coaxial line b) Rectangular waveguide c) Stripline d) Circular waveguide 24. A waveguide section in a microwave circuit will act as a a) Low-pass filter b) Band-pass filter ECE Dept, Sreyas Institute of Engineering & Technology
c) High-pass filter
[ ] d) Band-reject filter Microwave Engineering
Objective Question Bank
Unit 1
25. Microwave antenna aperture efficiency depends on a) Feed Pattern b) Antenna Aperture c) Surface losses 26. Microwave frequency range extends from a) 3 MHz to 30 MHz c) 300 MHz to 3000 MHz
[ ] d) Low side lobe level [
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b) 30 MHz to 300 MHz d) 500 MHz to 30000 MHz
27. At microwave frequencies the size of the antenna becomes a) Very large b) Large c) Small
d) Very Small
28. The phenomenon of microwave signals following the curvature of earth is known as a) Faraday effect b) Ducting c) Wave tilt d) Troposcatter
29. In microwave communication links, the rain drop attenuation experienced is mainly due to a) Absorption of microwave energy by water vapour b) resonance absorption of atomic vibration in water molecules c) scattering of microwaves by collection of water drops d) refraction of microwaves through liquid-drop lenses formed by rain 30) Which of the following is the dominant mode in TE wave? a) TE00 b) TE01 c) TE11
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TE10
Note: F il l th e foll owing blanks with suitable answer
31. The dominant mode attenuation factor due to finite conductivity (σ) of the waveguide walls is proportional to________. 32. At the cut-off frequency, the dominant mode characteristic impedance of a rectangular waveguide is _______________. 33. Typical frequency range of X-band is ____________G Hz . 34. At the cut-off frequency, the TM mode characteristic impedance of a rectangular waveguide is _ 11
_______ ohms. 35. The mode with the lowest cutoff frequency in a particular guide is called the __________mode . 36. When microwave signals follow the curvature of the earth this is known as ___________ . 37. When electromagnetic waves are reflected at an angle from a wall, their wavelength along the wall is _________________ in the actual direction of propagation. 38. To reduce loses at high frequencies, wave guides are plated with _____________. 39. A waveguide below cut-off is also called ______________ .
ECE Dept, Sreyas Institute of Engineering & Technology
Microwave Engineering
Objective Question Bank
Unit 1
40. _____________Mode exists in TM wave of rectangular waveguide as dominant mode. 41. Wave impedance for TM wave in rectangular guide in Z TM= _________________. 42. The Helmholt z’s wave equation for TE & TM wave travelling in ‘Z’ direction of a wave guides are ___________________. 43. Hollow _______________are commonly used as transmission lines at frequencies above 5 GHz. 44. All the TM
0m
and TM
1m
modes are degenerate in a uniform __________________waveguide.
45. All intersection between electric and magnetic field lines in a waveguide is _____________.
Key: 1. a
2. d
3. d
4. b
5. c
6. a
7. c
8. c
9. a
10. a
11. b
12. b
13. b
14. a
15. b
16.d
17.a
18.c
19.c
20. c
21. b
22.c
23.b
24.c
25.b
26.d
27.d
28. b
29. a
30. d
31. √ (1/ σ)
32. Infinity
33. 8 to 12
34. Zero
35. Dominant
36. Ducting
37. Greater than
38. Gold
39. Piston attenuator
40. TM 11
41. η / √1-(λ0/ λc)2
42. Δ2Hz=0 &Δ2Ez=0
43. waveguides_or tubes
44. Rectangular
45. Perpendicular ***
ECE Dept, Sreyas Institute of Engineering & Technology
