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Multiple Choice Objective Question On Power System Part 1

Hello Engineers.

Q.1 Feeder is designed mainly from the point of view of-

A. Its current carrying capacity
B. Voltage drop in it
C. Operating voltage
D. Operating Frequency

Ans: A


Q.2 Distributors are designed from the point of view of -

A. Its current carrying capacity
B. Operating voltage
C. Voltage drop in it
D. Operating frequency

Ans: C

Q.3 Transmission and distribution of electric power by underground system is superior to overhead system in respect of-

A. Apperance and public safety
B. Maintenance cost
C. Frequency of faults, power failure and accidents
D. All of the above

Ans: D

Q.4 The main drawback(s) of underground system over overhead system is/are-

A. Exposure to lighting
B. Heavy initial cost
C. Exposure to atmospheric hazards such as smoke, ice, wind etc.
D. Inductive interference between power and commuication circuit

Ans: B

Q.5 The main drawback of ovehead system over underground syste is-

A. Underground system is more flexible than overhead system
B. Higher charging current
C. Surge problem
D. High initial cost

Ans: C

Q.6 By increasing the transmission voltage to double of its original value the same power can be dispatched keeping the line loss-

A. Equal to original value
B. Half the original value
C. Double the original value
D. One fourth of original value

Ans: D

Q.7 For the same voltage drop, increasing the voltage of a distributor n time-

A. Reduces the x section of the conductor by n times
B. Increases the x section of the conductor by n times
C. Reduces the x section of conductor by n^2 times
D. Increases the x section of the conductor by n^2 times

Ans: A


Q.8 The volume of copper required for an ac transmission line is inversely proportional to-

A. Current
B. Voltage
C. Power factor
D. Both b and c

Ans: D

Q.9 Improving power factor-

A. Reduces current for a given output
B. Increases losses in line
C. Increases the cost of station equipment
D. None

Ans: A

Q.10 For the same conductor length, same amount of power, same lnsse sand same maximum voltage to earth, which system requires minimum conductor area-

A. Single phase ac
B. 3 phase ac
C. 2 wire ac
D. 3 wire ac

Ans: D

Q. 11 Transmission line connects-

A. Generating station to a switching station
B. Stepdown transformer station to service transformer banks
C. Distribution transformer to consumer premises
D. Service points to consumer permises

Answer: A

Q.12 A 3 phase 4 wire system is commonly used for-

A. Primary distribution
B. Secondary distribution
C. Primary transmission
D. Secondary transmission

Ans: B

Q.13 The rated voltage of a 3 phase power system is given as-

A. rms phase voltage
B. peak phase voltage
C. peak line to line voltage
D. rms line to line voltage

Ans: D

Q.14 Which of the following is usually not the generating voltage-

A. 6.6 kV
B. 9.9 kV
C. 11kV
D. 13.2kV

Ans:B

Q.15 In a transmission system the feeder supplies power to-

A. Transformer substations
B. Service mains
C. Distributors
D. All

Ans: C

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