22. The topmost wire in a distribution line is
A. neutral wire
B. earth wire
C. phase wire
D. any of these
23. Sheaths are used in power cables to
A. provide adequate insulation
B. increase the strength of the cable
C. prevent moisture from entering the cable
D. none of these
24. Pin insulators are normally used for voltages upto
A. 30 kV
B. 50 kV
C. 70 kV
D. 100 kV
25. Charging current in a transmission line
A. increases the line losses
B. decreases the line losses
C. does not effect the line losses
D. none of these
26. Transposition of conductors in transmission line system is done when
A. the conductors are not spaced equilaterally
B. the conductors are spaced equilaterally
C. a telephone line runs parallel to power line
D. none of these
27. For the same power transmission, if the transmitted voltage increases by factor n, the size of the conductor gets multiplied by factor
A. 1/n2
B. n2
C. 1/n3
D. n3
28. The Kelvin's law is limited because which of the following assumption made in it is only partly true?
A. load factor is uniform
B. annual charges are of the form P1 + aP2
C. both (a) and (b) above
D. none of/the above
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