Assuming constant transmission efficiency, if voltage is increased ‘n’ times, the size of the conductor would be

Increased to n2 that of the original

Reduced to 1/n2 that of the original

Increased to n2 that of the original

Reduced to 1/n that of the original

Increased to n times that of the original

As the cable length increases, there is

more insulation resistance and less leakage current

less insulation resistance and more leakage current

more insulation resistance and less leakage current

less insulation resistance and less leakage current

more insulation resistance and more leakage current

ACSR conductor means________.

Aluminium conduit steel reinforced

Aluminium conductor steel reinforced

Aluminium conduit steel reinforced

In AC transmission system the load current is:

directly proportional to power factor

inversely proportional to square of power factor

inversely proportional to power factor

directly proportional to power factor

Peterson coil is used for :

connecting interconnected systems

Directions: It consists of two statements, one labeled as the ‘Statement (I)’ and the other as ‘Statement (II)’. Examine these two statements carefully and select the answer using the codes given below:Statement (I): The expression for the value of inductance L per conductor of an unsymmetrically spaced 3-phase overhead transmission line contains an imaginary term.Statement (II): The presence of the imaginary term is due to the mutual inductance between the phase conductors and can be eliminated by symmetrically transposing the three line-conductors along the length of the line.

Statement (I) and Statement (II) are individually true but statement (II) is not the correct explanation of statement (I)

Statement (I) and Statement (II) are individually true and statement (II) is the correct explanation of statement (II)

Statement (I) and Statement (II) are individually true but statement (II) is not the correct explanation of statement (I)

Statement (I) is true but statement (II) is false

Statement (I) is false but statement (II) is true

On 132 kV transmission lines, some particle type of insulator is used. What is the name given to it?

Pin and shackle type insulators

A long transmission line terminated at its characteristics impendence will have

Only reflected wave but no incident wave

A reflected wave with double the amplitude of that of the incident wave.

A reflected wave with half the amplitude of that of the incident wave.

Only incident wave but no reflected wave

Only reflected wave but no incident wave

In transmission lines, the effective resistance of a conductor is increased by

Corona effect and Proximity effect

Proximity effect and Skin effect

Corona effect and Proximity effect

Primary reason of using bundle conductor is

to increase the power transfer capability

Directions: It consists of two statements, one labelled as the ‘Statement (I)’ and the other as ‘Statement (II)’. You are to examine these two statements carefully and select the answer using the codes given below:Statement (I): Tower to ground impedance must be kept high.Statement (II): High impedance produces high voltage at the insulator disc.

Both Statement (I) and Statement (II) are individually true and Statement (II) is the correct explanation of Statement (I)

Both Statement (I) and Statement (II) are individually true but Statement (II) is NOT the correct explanation of Statement (I)

Statement (I) is true but Statement (II) is false

Statement (I) is false but Statement (II) is true

Most severe non-uniform field is developed with

plate-rod electrode arrangement

two sphere electrode arrangement

point-point electrode arrangement

plate-rod electrode arrangement

two parallel plate electrode arrangement

If sag on a transmission is increase, the tension will:

sometimes increase and sometimes decrease

In a transmission system, the cost of lost energy is ______.

Directly proportional to the square of current

Inversely proportional to the square of current

Directly proportional to the square of voltage

Inversely proportional to the square of voltage

Cross-linked Polyethylene (XLPE) cable has

good impulse dielectric strength

high-thermal dissipation property

Power factor is increased by

Under excited synchronous motor

A 10 km long lossless transmission line has a reactance of 0.3 Ω/m and negligible shunt capacitance. The value of \(\left[ {\begin{array}{*{20}{c}} A&B\\ C&D \end{array}} \right]\) is.

\(\left[ {\begin{array}{*{20}{c}} {j3}&0\\ 1&1 \end{array}} \right]\)

\(\left[ {\begin{array}{*{20}{c}} 1&0\\ {j3}&1 \end{array}} \right]\)

\(\left[ {\begin{array}{*{20}{c}} 1&0\\ {0.3}&1 \end{array}} \right]\)

\(\left[ {\begin{array}{*{20}{c}} 1&{j3}\\ 0&1 \end{array}} \right]\)

\(\left[ {\begin{array}{*{20}{c}} {j3}&0\\ 1&1 \end{array}} \right]\)

517 + Mcqs in Transmission And Distribution in Electrical Engineering Page 3 McqOptions

101.	Assuming constant transmission efficiency, if voltage is increased ‘n’ times, the size of the conductor would be
A.	Reduced to 1/n2 that of the original
B.	Increased to n2 that of the original
C.	Reduced to 1/n that of the original
D.	Increased to n times that of the original
Answer» B. Increased to n2 that of the original

Discussion

102.	An equilaterally spaced 3 phase transmission line has a total corona loss of 30 kW at 112 kV, 50 Hz. If the frequency is changed to 60 Hz, the total corona loss will be:
A.	32 kW
B.	34 kW
C.	36 kW
D.	38 kW
Answer» C. 36 kW

Discussion

103.	Consider the two-bus power system network with given loads as shown in the figure. All the values shown in the figure are in per unit. The reactive power supplied by generator G1 and G2 are QG1 and QG2 respectively. The per unit values of QG1, QG2, and line reactive power loss (Qloss) respectively are
A.	5.00, 12.68, 2.68
B.	6.34, 10.00, 1.34
C.	6.34, 11.34, 2.68
D.	5.00, 11.34, 1.34
Answer» D. 5.00, 11.34, 1.34

Discussion

104.	Consider the following statements regarding aluminium conductor steel reinforced conductors in transmission lines.State whether these statements are true or false.(a) It is cheaper than copper conductors of equal resistance.(b) Corona losses are reduced in it because of the larger diameter of the conductor.(c) It has lesser mechanical strength, so it needs more support for a particular length of transmission line.
A.	(a) False, (b) True, (c) False
B.	(a) False, (b) True, (c) True
C.	(a) True, (b) True, (c) False
D.	(a) True, (b) True, (c) True
Answer» D. (a) True, (b) True, (c) True

Discussion

105.	As the cable length increases, there is
A.	less insulation resistance and more leakage current
B.	more insulation resistance and less leakage current
C.	less insulation resistance and less leakage current
D.	more insulation resistance and more leakage current
Answer» B. more insulation resistance and less leakage current

Discussion

106.	Disadvantage of low power factor is
A.	Large kW rating
B.	High power factor
C.	Large kVA rating
D.	None of the above
Answer» D. None of the above

Discussion

107.	A power factor meter connected in a circuit indicates pf of 0.6 lagging. To improve the power factor, we have to insert the following component in the circuit.
A.	Inductors
B.	Both inductor and resistors
C.	Capacitors
D.	Resistors
Answer» D. Resistors

Discussion

108.	Bulk power transmission over long HVDC lines is preferred because of
A.	Low cost of HVDC terminal
B.	No harmonic losses
C.	Minimum line power losses
D.	Simple protection
Answer» D. Simple protection

Discussion

109.	Basic impulse level of 11 kV distribution system as per IS specification is
A.	100 kVp
B.	85 kVp
C.	75 kVp
D.	45 kVp
Answer» D. 45 kVp

Discussion

110.	A single phase overhead transmission line delivers a power of 5500 kW to a load at 11 kV. The receiving end voltage leads the current by 45°. The resistance and the inductive reactance of the transmission line are 10 Ω and 10 Ω respectively. The sending end voltages is
A.	12 kV
B.	15 kV
C.	21 kV
D.	22 kV
Answer» D. 22 kV

Discussion

111.	In aluminium (ACSR) conductors, steel core is provided to
A.	Compensate for skin effect
B.	Neutralise proximity effect
C.	Reduce line inductance
D.	Increase the tensile strength
Answer» E.

Discussion

112.	_____ earthing is the best form of earthing and is very cheap in cost.
A.	Rod
B.	Plate
C.	Pipe
D.	strip
Answer» D. strip

Discussion

113.	ACSR conductor means________.
A.	All conductor Steel Reinforced
B.	Aluminium conductor steel reinforced
C.	Aluminium conduit steel reinforced
D.	All conduit steel reinforced
Answer» C. Aluminium conduit steel reinforced

Discussion

114.	In AC transmission system the load current is:
A.	inversely proportional to square of power factor
B.	inversely proportional to power factor
C.	directly proportional to power factor
D.	independent of power factor
Answer» C. directly proportional to power factor

Discussion

115.	A travelling wave of magnituide 100 V in transmission line of surge impedance 400 Ω passes into a cable of surge impedance 50 Ω. What will be the magnitude of the wave while travelling in the cable?
A.	800 V
B.	100 V
C.	20 V
D.	12.5 V
Answer» D. 12.5 V

Discussion

116.	Earth electrode used in plate earthing is a _______
A.	Plate
B.	Pipe
C.	Rod
D.	Grid
Answer» B. Pipe

Discussion

117.	Peterson coil is used for :
A.	shunt compensation of lines
B.	reduce fault currents
C.	grounding of system neutral
D.	connecting interconnected systems
Answer» D. connecting interconnected systems

Discussion

118.	Directions: It consists of two statements, one labeled as the ‘Statement (I)’ and the other as ‘Statement (II)’. Examine these two statements carefully and select the answer using the codes given below:Statement (I): The expression for the value of inductance L per conductor of an unsymmetrically spaced 3-phase overhead transmission line contains an imaginary term.Statement (II): The presence of the imaginary term is due to the mutual inductance between the phase conductors and can be eliminated by symmetrically transposing the three line-conductors along the length of the line.
A.	Statement (I) and Statement (II) are individually true and statement (II) is the correct explanation of statement (II)
B.	Statement (I) and Statement (II) are individually true but statement (II) is not the correct explanation of statement (I)
C.	Statement (I) is true but statement (II) is false
D.	Statement (I) is false but statement (II) is true
Answer» B. Statement (I) and Statement (II) are individually true but statement (II) is not the correct explanation of statement (I)

Discussion

119.	If a power of 30 MW is to be transmitted over a distance of 160 km the desirable transmission voltage will be:
A.	33 kV
B.	66 kV
C.	110 kV
D.	220 kV
Answer» D. 220 kV

Discussion

120.	Grading of cable means distribution of dielectric material in such a way that the difference between Emax and Emin is
A.	reduced
B.	increased
C.	increased to infinity
D.	None of the above
Answer» B. increased

Discussion

121.	A uniform two-wire DC distributor that is 200 m long is loaded with 2 amperes/meter. Resistance of single wire is 0.3 Ω/km. Calculate the maximum voltage drop if the distributor is fed from one end.
A.	12 V
B.	6 V
C.	24 V
D.	36 V
Answer» B. 6 V

Discussion

122.	Out of the following dielectric materials which one has the highest thermal endurance?
A.	PVC
B.	XLPE
C.	Teflon
D.	Transformer oil
Answer» D. Transformer oil

Discussion

123.	In a basic transmission line, the voltage at the receiving end without load is 660 V; and it is 420 V with full load. What is the percentage of voltage regulation?
A.	77%
B.	67%
C.	57%
D.	47%
Answer» D. 47%

Discussion

124.	On 132 kV transmission lines, some particle type of insulator is used. What is the name given to it?
A.	Pin type insulators
B.	Disc type insulators
C.	Shackle type insulators
D.	Pin and shackle type insulators
Answer» C. Shackle type insulators

Discussion

125.	In transmission line generally, the wires used are
A.	ACSR wires
B.	Copper wires
C.	Iron wires
D.	Aluminium wires
Answer» B. Copper wires

Discussion

126.	Power quality problems originates from
A.	power plant
B.	substation
C.	transmission lines
D.	All of the above
Answer» E.

Discussion

127.	A long transmission line terminated at its characteristics impendence will have
A.	A reflected wave with double the amplitude of that of the incident wave.
B.	A reflected wave with half the amplitude of that of the incident wave.
C.	Only incident wave but no reflected wave
D.	Only reflected wave but no incident wave
Answer» D. Only reflected wave but no incident wave

Discussion

128.	________ is used to manufacture stay wire, earth wire, and structural components.
A.	Hard drawn copper
B.	Nichrome
C.	Cadmium copper
D.	Galvanised steel
Answer» E.

Discussion

129.	Ferranti effect in long transmission lines is due to the effect of
A.	Line reactance
B.	Line capacitance
C.	Line resistance
D.	None of the above
Answer» C. Line resistance

Discussion

130.	For a uniformly loaded dc distribution fed at one end, the maximum voltage drop is found to be 10 V. If it is fed at both ends at the same voltage, the maximum voltage drop would be
A.	2.5 V
B.	5.0 V
C.	10 V
D.	20 V
Answer» B. 5.0 V

Discussion

131.	In order to improve the voltage regulation of a supply system, wires used in wiring the system should have ______.
A.	High insulation resistance
B.	More area of cross section
C.	Less area of cross section
D.	More specific resistance
Answer» C. Less area of cross section

Discussion

132.	In transmission lines, the effective resistance of a conductor is increased by
A.	Proximity effect and Skin effect
B.	Corona effect and Proximity effect
C.	Corona effect and Skin effect
D.	Proximity effect only
Answer» B. Corona effect and Proximity effect

Discussion

133.	Maximum safe temperature for class H insulation material is
A.	160°C
B.	180°C
C.	200°C
D.	220°C
Answer» C. 200°C

Discussion

134.	Primary reason of using bundle conductor is
A.	to reduce line inductance
B.	to improve stability limit
C.	to increase the power transfer capability
D.	to reduce corona
Answer» E.

Discussion

135.	Directions: It consists of two statements, one labelled as the ‘Statement (I)’ and the other as ‘Statement (II)’. You are to examine these two statements carefully and select the answer using the codes given below:Statement (I): Tower to ground impedance must be kept high.Statement (II): High impedance produces high voltage at the insulator disc.
A.	Both Statement (I) and Statement (II) are individually true and Statement (II) is the correct explanation of Statement (I)
B.	Both Statement (I) and Statement (II) are individually true but Statement (II) is NOT the correct explanation of Statement (I)
C.	Statement (I) is true but Statement (II) is false
D.	Statement (I) is false but Statement (II) is true
Answer» E.

Discussion

136.	Most severe non-uniform field is developed with
A.	two sphere electrode arrangement
B.	point-point electrode arrangement
C.	plate-rod electrode arrangement
D.	two parallel plate electrode arrangement
Answer» C. plate-rod electrode arrangement

Discussion

137.	A three-phase four-wire system is used for:
A.	secondary distribution
B.	generation station
C.	transmission
D.	primary distribution
Answer» B. generation station

Discussion

138.	In skin effect the skin depth is proportional to (f is frequency)
A.	f
B.	\(\frac{1}{{\sqrt f}}\)
C.	\(\frac{1}{f}\)
D.	√f
Answer» C. \(\frac{1}{f}\)

Discussion

139.	High voltage transmission lines use ________.
A.	Pin insulators
B.	Suspension insulators
C.	Shackle insulator
D.	None of these
Answer» C. Shackle insulator

Discussion

140.	If sag on a transmission is increase, the tension will:
A.	decrease
B.	increase
C.	not be affected at all
D.	sometimes increase and sometimes decrease
Answer» B. increase

Discussion

141.	In a transmission system, the cost of lost energy is ______.
A.	Directly proportional to the square of current
B.	Inversely proportional to the square of current
C.	Directly proportional to the square of voltage
D.	Inversely proportional to the square of voltage
Answer» E.

Discussion

142.	For a medium length transmission line, A is
A.	equal to B
B.	equal to C
C.	equal to D
D.	not equal to any of the these
Answer» D. not equal to any of the these

Discussion

143.	In a transmission system if V is the transmission voltage, weight of copper needed is proportional to ______.
A.	V
B.	1/V2
C.	V2
D.	1/V
Answer» C. V2

Discussion

144.	Normally, __________ material is used as armouring.
A.	magnetic
B.	non-magnetic
C.	laminated
D.	None of the above
Answer» B. non-magnetic

Discussion

145.	Calculate the increase in resistance and weight due to spiraling of the conductor having a diameter of each strand of 2 cm and a number of layers excluding central strand is one. Lay length is 40 cm.
A.	0.16%
B.	0.28%
C.	0.36%
D.	0.52%
Answer» C. 0.36%

Discussion

146.	Cross-linked Polyethylene (XLPE) cable has
A.	good impulse dielectric strength
B.	inert to chemical reaction
C.	high-thermal dissipation property
D.	All of the above
Answer» E.

Discussion

147.	For a transmission line with resistance R and reactance X and negligible capacitance generalized constant A is:
A.	1
B.	R - jX
C.	R + jX
D.	0
Answer» B. R - jX

Discussion

148.	Power factor is increased by
A.	Series capacitor
B.	Capacitor in parallel to load
C.	Under excited synchronous motor
D.	All of the above
Answer» C. Under excited synchronous motor

Discussion

149.	A 10 km long lossless transmission line has a reactance of 0.3 Ω/m and negligible shunt capacitance. The value of \(\left[ {\begin{array}{*{20}{c}} A&B\\ C&D \end{array}} \right]\) is.
A.	\(\left[ {\begin{array}{*{20}{c}} 1&0\\ {j3}&1 \end{array}} \right]\)
B.	\(\left[ {\begin{array}{*{20}{c}} 1&0\\ {0.3}&1 \end{array}} \right]\)
C.	\(\left[ {\begin{array}{*{20}{c}} 1&{j3}\\ 0&1 \end{array}} \right]\)
D.	\(\left[ {\begin{array}{*{20}{c}} {j3}&0\\ 1&1 \end{array}} \right]\)
Answer» D. \(\left[ {\begin{array}{*{20}{c}} {j3}&0\\ 1&1 \end{array}} \right]\)

Discussion

150.	Pin insulators can never be used above:
A.	22 kV
B.	11 kV
C.	33 kV
D.	6.6 kV
Answer» D. 6.6 kV

Discussion

Explore topic-wise MCQs in Electrical Engineering.

Assuming constant transmission efficiency, if voltage is increased ‘n’ times, the size of the conductor would be

An equilaterally spaced 3 phase transmission line has a total corona loss of 30 kW at 112 kV, 50 Hz. If the frequency is changed to 60 Hz, the total corona loss will be:

As the cable length increases, there is

Disadvantage of low power factor is

A power factor meter connected in a circuit indicates pf of 0.6 lagging. To improve the power factor, we have to insert the following component in the circuit.

Bulk power transmission over long HVDC lines is preferred because of

Basic impulse level of 11 kV distribution system as per IS specification is

A single phase overhead transmission line delivers a power of 5500 kW to a load at 11 kV. The receiving end voltage leads the current by 45°. The resistance and the inductive reactance of the transmission line are 10 Ω and 10 Ω respectively. The sending end voltages is

In aluminium (ACSR) conductors, steel core is provided to

_____ earthing is the best form of earthing and is very cheap in cost.

ACSR conductor means________.

In AC transmission system the load current is:

A travelling wave of magnituide 100 V in transmission line of surge impedance 400 Ω passes into a cable of surge impedance 50 Ω. What will be the magnitude of the wave while travelling in the cable?

Earth electrode used in plate earthing is a _______

Peterson coil is used for :

If a power of 30 MW is to be transmitted over a distance of 160 km the desirable transmission voltage will be:

Grading of cable means distribution of dielectric material in such a way that the difference between Emax and Emin is

A uniform two-wire DC distributor that is 200 m long is loaded with 2 amperes/meter. Resistance of single wire is 0.3 Ω/km. Calculate the maximum voltage drop if the distributor is fed from one end.

Out of the following dielectric materials which one has the highest thermal endurance?

In a basic transmission line, the voltage at the receiving end without load is 660 V; and it is 420 V with full load. What is the percentage of voltage regulation?

On 132 kV transmission lines, some particle type of insulator is used. What is the name given to it?

In transmission line generally, the wires used are

Power quality problems originates from

A long transmission line terminated at its characteristics impendence will have

________ is used to manufacture stay wire, earth wire, and structural components.

Ferranti effect in long transmission lines is due to the effect of

For a uniformly loaded dc distribution fed at one end, the maximum voltage drop is found to be 10 V. If it is fed at both ends at the same voltage, the maximum voltage drop would be

In order to improve the voltage regulation of a supply system, wires used in wiring the system should have ______.

In transmission lines, the effective resistance of a conductor is increased by

Maximum safe temperature for class H insulation material is

Primary reason of using bundle conductor is

Most severe non-uniform field is developed with

A three-phase four-wire system is used for:

In skin effect the skin depth is proportional to (f is frequency)

High voltage transmission lines use ________.

If sag on a transmission is increase, the tension will:

In a transmission system, the cost of lost energy is ______.

For a medium length transmission line, A is

In a transmission system if V is the transmission voltage, weight of copper needed is proportional to ______.

Normally, __________ material is used as armouring.

Calculate the increase in resistance and weight due to spiraling of the conductor having a diameter of each strand of 2 cm and a number of layers excluding central strand is one. Lay length is 40 cm.

Cross-linked Polyethylene (XLPE) cable has

For a transmission line with resistance R and reactance X and negligible capacitance generalized constant A is:

Power factor is increased by

A 10 km long lossless transmission line has a reactance of 0.3 Ω/m and negligible shunt capacitance. The value of \(\left[ {\begin{array}{*{20}{c}} A&B\\ C&D \end{array}} \right]\) is.

Pin insulators can never be used above: