Microwave Devices and Circuits MCQs

Question 1

Waveguides are considered superior to coaxial lines in the range

Accepted Answer

3 GHz to 100 GHz

Answer

30 MHz to 1 GHz

Answer

1 GHz to 3 GHz

Answer

100 GHzto 150 GHz

Question 2

Standard mismatching in microwave circuits have SWR from

Accepted Answer

1.2 :1 to2: 1

Answer

0.5 : 1 to 2 : 1

Answer

1 : 0.5 to 2 : 1

Answer

1.33 : lto2 : 1

Question 3

Magic tee is a combination of

Accepted Answer

two Hs and one E plane tee

Answer

two Hs and one plane tee

Answer

one H and two E plane tees

Answer

none of the above

Question 4

When electromagnetic waves are reflected at an angle from a wall their wavelength along the wall is

Accepted Answer

greater than in the actual direction of propagation

Answer

the same as in free space

Answer

the same as the wavelength perpendicular to the wall

Answer

shortened because of the Doppler effect

Question 5

A signal propagated in a waveguide has a full wave of electric intensity change between the two further walls and no component of the electric filed in the direction of propagation. The mode is

Accepted Answer

TE2, 0

Answer

TE1,

Answer

TEI, 0

Answer

TM2, 3

Question 6

Which of the following diode is different from the remaining?

Accepted Answer

Backward diode

Answer

Hot carrier diode

Answer

ESbAR diode

Answer

Schottky carrier diode

Question 7

The efficiency of an ideal klystron is closer to

Accepted Answer

50%

Answer

25%

Answer

75%

Answer

90%

Question 8

For a rectangular waveguide with a = 2 cm and b = 1 cm, the cut-off wavelength for (TE10) mode would be

Accepted Answer

4 cm

Answer

2 cm

Answer

1 cm

Answer

none of these

Question 9

What is perculiar about a TEN mode propagating in a circular waveguide?

Accepted Answer

It has least attenuation and attenuation decreases with increase in frequency

Answer

It is the dominant mode

Answer

It is used for long microwave communication links

Answer

It has the largest attenuation