Power System - I (3140914) MCQs

MCQs of Electrical Supply Systems

Showing 61 to 69 out of 69 Questions
61.
Which of the following distribution system is not normally used?
(a) Three phase 3-wire AC system
(b) Three phase 4-wire AC system
(c) Single phase 3-wire AC system
(d) Single phase 2-wire AC system
Answer:

Option (c)

62.
The approximate cost ration of 220 kV underground cable transmission and 220 kV over head transmission
(a) 50
(b) 25
(c) 13
(d) 5
Answer:

Option (c)

63.
With the same maximum voltage to earth, which of the following AC system with 0.8 power factor will need more copper in comparison to DC 2-wire system
(a) Single phase 2-wire (midpoint earthed)
(b) Single phase 3-wire
(c) Three phase 3-wire AC system
(d) Three phase 4-wire AC system
Answer:

Option (d)

64.
With the same maximum voltage between conductor, the ratio of copper volumes needed in three phase, 3-wire system and single phase, 2-wire system is
(a) 4/3
(b) 3/4
(c) 5/3
(d) 3/5
Answer:

Option (b)

65.
The main reason for using high voltage for long distance power transmission is
(a) Reduction in transmission losses
(b) Reduction in time of transmission
(c) Increase in transmission reliability
(d) None of above
Answer:

Option (a)

66.
The most economical voltage for transmission over given power for known distance by overhead transmission system is
(a) 0.3 kV/Km
(b) 0.6 kV/Km
(c) 1.5 kV/Km
(d) 2.5 kV/Km
Answer:

Option (b)

67.
For transmission of power over a distance of 500 km, the transmission voltage should be
(a) 11 to 22 kV
(b) 33 to 66 kV
(c) 66 to 110 kV
(d) 132 to 220 kV
Answer:

Option (d)

68.
66 kV is suitable for transmission power over
(a) 30 km
(b) 60 km
(c) 120 km
(d) 200 km
Answer:

Option (b)

69.
3 MW power is transmitted over a distance of 30 km, the desirable transmission voltage is
(a) 11 kV
(b) 33 kV
(c) 66 kV
(d) 3.3 kV
Answer:

Option (c)

Showing 61 to 69 out of 69 Questions