85. Equal area criterion gives the information regarding
A. stability region
B. absolute stability
C. relative stability
D. swing curves

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86. One current transformer (CT) is mounted over a 3-phase 3-core cable with its sheath and armour removed from the portion covered by the CT. An ammeter placed in the CT secondary would measure
A. the positive sequence current
B. the negative sequence current
C. the zero sequence current
D. three times the zero sequence

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87. When bundle conductors are used in place of single conductors, the effective inductance and capacitance will respectively
A. increase and decrease
B. decrease and increase
C. decrease and remain unaffected
D. remain unaffected and increase

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88. A string insulator has 4 units. The voltage across the bottom-most unit is 33.33% of the total voltage. Its string efficiency is
A.25%
B.33.33%
C.66.70%
D.75%

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89. The design of isulation for systems above 400kV, is based upon
A. lightning overvoltage
B. switching surges
C. system Voltage level
D. system load level

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90. The power transmission capability of bipolar lines is approximately
A. half that of 3-phase single circuit line
B. the same as that of 3-phase single circuit line
C. twice that of 3-phase single circuit line
D. thrice that of 3-phase single circuit line

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91. In which one of the following models of transmission lines, is the full charging current assumed to low over half the length of the line only?
A. Equivalent-it
B. Short line
C. Nominal-it
D. Nominal-T

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