Electromagnetism MCQs

Question 1

In a wave guide, attenuation near the el!toff frequency is

Accepted Answer

Zero

Answer

low

Answer

high

Answer

very high

Question 2

A transmission line of characteristic impedance Z0 is terminated in Z.. The input impedance is

Accepted Answer

Z02

Answer

?

Answer

2Z0

Answer

4Z0

Question 3

Compared to equivalent transmission lines at low frequencies, waveguides are

Accepted Answer

both and above

Answer

less lossy

Answer

able to carry more power

Answer

lighter in weight

Question 4

Characteristic wave impedance is

Accepted Answer

either or above

Answer

?

Answer

167

Answer

Ex/Hy

Question 5

The wavelength of an EM wave after reflection at an angle on a surface

Accepted Answer

increases in the actual direction of propagation

Answer

decreases in the actual direction of propagation

Answer

remains the same as the wavelength perpendicular to the surface

Answer

remains the same as in free space.

Question 6

Impedance inversion is achieved by use of

Accepted Answer

quarter wave line

Answer

half wave line

Answer

full wave line

Answer

Balun transformer

Question 7

Disturbance due to adjacent power line is called

Accepted Answer

inductive disturbance

Answer

cross talk

Answer

cross fire

Answer

noise

Question 8

Disturbance caused by adjacent telephone line is called

Accepted Answer

cross talk

Answer

cross fire

Answer

inductive disturbance

Answer

noise

Question 9

A transmision line of length nA./4 (n is integer) is short circuited at the far end. The input impedance is

Accepted Answer

infinite

Answer

zero

Answer

Z0

Answer

Z0/2