Transmission Line Analysis: Interactive Learning Quizzes

Question 1

A 50-ohm transmission line is terminated with a load impedance of 25 - j50 ohms. Calculate the reflection coefficient at the load.

Accepted Answer

0.75

Answer

0.25

Answer

0.5

Answer

1.0

Question 2

When is the power transmitted on a transmission line maximum?

Accepted Answer

When the line is matched to the load

Answer

When the line is open-circuited

Answer

When the line is short-circuited

Answer

When the line is terminated in a pure reactance

Question 3

Which of the following factors does NOT affect the characteristic impedance of a transmission line?

Accepted Answer

Length of the line

Answer

Conductor spacing

Answer

Conductor diameter

Answer

Insulator material

Question 4

Which of the following is NOT a type of transmission line?

Accepted Answer

Optical fiber

Answer

Coaxial line

Answer

Twisted pair

Answer

Microstrip line

Question 5

A transmission line is matched to its load. What is the value of the reflection coefficient at the load?

Accepted Answer

0

Answer

0.5

Answer

1

Answer

2

Question 6

In a transmission line, which parameter primarily determines the maximum power that can be transmitted without distortion?

Accepted Answer

Surge impedance loading

Answer

Characteristic impedance

Answer

Line inductance

Answer

Line capacitance

Question 7

Which characteristic is NOT associated with transmission lines?

Accepted Answer

Lumped inductance

Answer

Distributed inductance

Answer

Distributed capacitance

Answer

Distributed resistance

Question 8

If a transmission line is terminated with an open circuit, its input impedance is:

Accepted Answer

Infinite

Answer

Zero

Answer

Equivalent to the characteristic impedance

Answer

Half of the characteristic impedance

Question 9

Which factor primarily influences the wavelength on a transmission line?

Accepted Answer

Frequency

Answer

Propagation velocity

Answer

Characteristic impedance

Answer

Line length

Question 10

The relationship between the reflection coefficient (Γ) and the standing wave ratio (SWR) is given by:

Accepted Answer

SWR = (1 + |Γ|) / (1 - |Γ|)

Answer

SWR = (1 - |Γ|) / (1 + |Γ|)

Answer

SWR = |Γ| / (1 - |Γ|)

Answer

SWR = (1 - |Γ|) / |Γ|

Question 11

The maximum power transmittable through a lossless transmission line is expressed as:

Accepted Answer

P = V²/Z₀

Answer

P = Z₀I²

Answer

P = V²/4Z₀

Answer

P = Z₀V²

Question 12

Increasing the frequency on a transmission line results in:

Accepted Answer

Increased propagation velocity

Answer

Decreased propagation velocity

Answer

Unchanged propagation velocity

Answer

Zero propagation velocity

Question 13

Which parameter quantifies the ratio of the incident wave voltage to the reflected wave voltage on a transmission line?

Accepted Answer

Reflection coefficient

Answer

Standing wave ratio

Answer

Input impedance

Answer

Voltage standing wave ratio

Question 14

For a lossless transmission line terminated with a load impedance (Z_L) equal to the characteristic impedance (Z_0), the input impedance (Z_in) is:

Accepted Answer

Z_in = Z_0

Answer

Z_in = 2Z_0

Answer

Z_in = 0

Answer

Z_in = -Z_0

Question 15

Which of the following factors does NOT influence the characteristic impedance of a transmission line?

Accepted Answer

Line length

Answer

Conductor material

Answer

Conductor spacing

Answer

Insulator permittivity

Question 16

For a transmission line with a standing wave ratio (SWR) of 3, the ratio of maximum voltage to minimum voltage along the line is:

Accepted Answer

3:1

Answer

1:2

Answer

2:1

Answer

1:3

Question 17

To minimize reflections on a transmission line, the load impedance (Z_L) should be matched to:

Accepted Answer

Resistive load equal to Z_0

Answer

Short circuit

Answer

Open circuit

Answer

Capacitive load

Question 18

The velocity of propagation (v) for a transmission line is primarily determined by:

Accepted Answer

Insulator material

Answer

Conductor material

Answer

Conductor spacing

Answer

Line length

Question 19

Which type of transmission line exhibits the lowest losses?

Accepted Answer

Fiber optic cable

Answer

Coaxial cable

Answer

Twisted pair cable

Answer

Waveguide

Question 20

Which of the following is NOT a unit of power commonly used in analyzing transmission lines?

Accepted Answer

Megajoules (MJ)

Answer

Watts (W)

Answer

Volt-Amperes Reactive (VAR)

Answer

Volt-Amperes (VA)

Question 21

In a transmission line, the ratio of active power (P) to reactive power (Q) is referred to as:

Accepted Answer

Power factor

Answer

SWR

Answer

Input impedance

Answer

Standing wave ratio

Question 22

The input impedance of a transmission line is given by which equation ?

Accepted Answer

Z_in = Z_0 * (1 + Γ) / (1 - Γ)

Answer

Z_in = Z_0 * (1 - Γ) / (1 + Γ)

Answer

Z_in = Z_0 * (Γ - 1) / (Γ + 1)

Answer

Z_in = Z_0 * (Γ + 1) / (Γ - 1)

Question 23

What is the condition for maximum power transfer in a transmission line ?

Accepted Answer

Z_in = Z_L

Answer

Z_in = -Z_L

Answer

Z_in = Z_0

Answer

Z_in = -Z_0

Question 24

What is the relationship between standing wave ratio (SWR) and reflection coefficient Γ ?

Accepted Answer

SWR = (1 + |Γ|) / (1 - |Γ|)

Answer

SWR = (1 - |Γ|) / (1 + |Γ|)

Answer

SWR = |Γ| / (1 - |Γ|)

Answer

SWR = (1 - |Γ|) / |Γ|

Question 25

What is the formula for calculating the characteristic impedance (Z₀) of a transmission line, given its inductance (L) and capacitance (C) per unit length?

Accepted Answer

Z₀ = √(L/C)

Answer

Z₀ = L + C

Answer

Z₀ = L/C

Question 26

When troubleshooting transmission lines, which parameter is most useful for detecting impedance mismatches and their impact on signal quality?

Accepted Answer

Standing Wave Ratio (SWR)

Answer

Voltage

Answer

Current

Answer

Input Impedance

Question 27

How does a higher quality factor (Q) of a transmission line affect signal distortion?

Accepted Answer

Reduces distortion

Answer

Increases distortion

Answer

Has no effect on distortion

Answer

Depends on the operating frequency

Question 28

A lossless transmission line with a characteristic impedance of 50 ohms has an input impedance of 50 ohms. What is the reflection coefficient on the line?

Accepted Answer

0

Answer

1

Answer

0.5

Answer

Infinite

Question 29

Which of the following factors does NOT affect the characteristic impedance of a transmission line?

Accepted Answer

Length

Answer

Insulator permittivity

Answer

Conductor radius

Answer

Spacing between conductors

Question 30

Which of the following is a method for matching the input impedance of a transmission line to the load impedance?

Accepted Answer

Using a matching transformer

Answer

Shorting the line at the load end

Answer

Increasing the length of the line

Question 31

A transmission line is impedance-matched to its load. What is the power reflection coefficient?

Accepted Answer

0

Answer

0.5

Answer

1

Answer

-1

Question 32

A transmission line with a length of λ/4 is terminated with a short circuit. What is the input impedance at the load end?

Accepted Answer

0 Ω

Answer

λ/4 Ω

Answer

λ Ω

Answer

λ/2 Ω

Question 33

What is the primary reason for matching the impedance of a transmission line to the impedance of an antenna?

Accepted Answer

To minimize power reflection and maximize power transfer.

Answer

To reduce the loss in the line.

Answer

To increase the bandwidth of the line.

Question 34

A transmission line with a characteristic impedance of 50 ohms is terminated with a load impedance of 100 ohms. What is the reflection coefficient at the load?

Accepted Answer

0.5

Answer

1.0

Answer

-0.5

Question 35

What is the primary function of a stub tuner when used with a transmission line?

Accepted Answer

To achieve impedance matching between the load and the transmission line.

Answer

To increase the power handling capacity of the transmission line.

Answer

To reduce the physical length of the transmission line.

Question 36

A transmission line is terminated with a purely reactive load. What is the phase angle of the reflection coefficient?

Accepted Answer

Either 90 degrees or -90 degrees

Answer

180 degrees

Answer

0 degrees

Answer

45 degrees

Question 37

A transmission line is considered matched to its load when the reflection coefficient is:

Accepted Answer

0

Answer

1

Answer

0.5

Answer

-1

Question 38

Which of the following characteristics defines a lossless transmission line?

Accepted Answer

The resistance per unit length of the line is zero.

Answer

The characteristic impedance is constant along the line.

Answer

The line is terminated with a matched load.

Answer

The reflection coefficient is zero.

Question 39

The velocity of propagation of an electromagnetic wave on a transmission line is primarily determined by:

Accepted Answer

The permittivity and permeability of the dielectric material surrounding the line.

Answer

The length of the transmission line.

Answer

The characteristic impedance of the line.

Question 40

If a transmission line is not matched to its load, what happens to the power transmitted?

Accepted Answer

Some of the power is reflected back towards the source.

Answer

The transmission line becomes lossless.

Answer

The voltage at the load is always higher than the voltage at the source.

Answer

The power transmitted to the load increases.

Question 41

What is the primary purpose of using a stub on a transmission line?

Accepted Answer

To cancel out reflections and achieve impedance matching.

Answer

To reduce the propagation velocity of the signal.

Answer

To increase the power handling capacity of the transmission line.

Question 42

A lossless transmission line with a characteristic impedance of 50 ohms has a length of 100 meters. It is terminated by a load impedance of 75 ohms. What is the reflection coefficient at the load end?

Accepted Answer

0.6

Answer

0.25

Answer

0.8

Answer

0.4

Question 43

A transmission line with a voltage standing wave ratio (VSWR) of 2.5 has a maximum voltage of 100 volts. What is the minimum voltage on the line?

Accepted Answer

40 volts

Answer

25 volts

Answer

75 volts

Answer

50 volts

Question 44

A transmission line is matched to its load. What is the power delivered to the load?

Accepted Answer

Maximum power

Answer

Half of the maximum power

Answer

Minimum power

Answer

None of the above

Question 45

A transmission line with a characteristic impedance of 100 ohms is terminated by a load impedance of 50 ohms. What is the input impedance of the line?

Accepted Answer

50 ohms

Answer

25 ohms

Answer

200 ohms

Answer

100 ohms

Question 46

A transmission line has a length of 50 meters and a propagation velocity of 2 x 10^8 meters per second. What is the wavelength of the signal on the line?

Accepted Answer

100 meters

Answer

25 meters

Answer

200 meters

Answer

50 meters

Question 47

A transmission line is operating at a frequency of 1 GHz. The line has a length of 10 meters and a propagation velocity of 3 x 10^8 meters per second. What is the phase shift experienced by the signal over the length of the line?

Accepted Answer

2π radians

Answer

0.5π radians

Answer

π radians

Answer

4π radians

Question 48

A transmission line has a characteristic impedance of 75 ohms. The line is terminated by a load impedance of 50 ohms. What is the standing wave ratio on the line?

Accepted Answer

1.5

Answer

0.25

Answer

0.5

Answer

2.0

Question 49

A transmission line is used to connect a transmitter to an antenna. The line has a length of 50 meters, a characteristic impedance of 50 ohms, and is terminated by a load impedance of 75 ohms. What is the reflection coefficient at the transmitter end?

Accepted Answer

0.25

Answer

1

Answer

0

Answer

-0.5

Question 50

A transmission line is used to connect a receiver to an antenna. The line has a length of 25 meters, a characteristic impedance of 75 ohms, and is terminated by a load impedance of 50 ohms. What is the voltage standing wave ratio on the line?

Accepted Answer

1.5

Answer

0.25

Answer

2.0

Answer

0.5

Question 51

A transmission line is used to connect a power amplifier to an antenna. The line has a length of 100 meters, a characteristic impedance of 50 ohms, and is terminated by a load impedance of 75 ohms. The power amplifier has an output power of 100 watts. What is the power delivered to the antenna?

Accepted Answer

66.67 watts

Answer

25 watts

Answer

50 watts

Answer

100 watts