76.

77.

78.

79.

80.

81.

82.

83.

Current chopping occurs in :
(^) Bulk oil circuit breaker (B)_ Air blast circuit breaker
(C) Minimum oil circuit breaker (D) All the above

The equal area criteria is used to obtain information about :
(A) transient stability (B) swing curves

(0) reactive power limit (D) _ short circuit current limit

The positive sequence and negative sequence voltages are equal ina:
(A) | line to line fault (B) _ single line to ground fault
(C) symmetrical fault (D) double line to ground fault

Calculate the plug setting multiplier of a 6A over current relay having a current setting of
150%, connected to a supply circuit through 420/6A CT when the circuit carries a fault
current of 4200A :

(ಸ) 6.67 (B) 46
(0 8 (D) 8.32

The voltage magnitude and voltage phase angle are specified ina:
(^) Load bus (B) Generator bus
(C) Swing bus (D) Voltage controlled bus

Find the number of revolutions made by a single phase energy meter when used to measure
the energy consumption by a 230 V, 0.8 pf, 10A load for 2 hours if the energy meter constant
is 750?

(A) 1440 (B) 1540

©) 1480 (D) 1880

Calculate the flux density of a moving coil voltmeter with 10Q resistance which gives full
scale deflection for 50mV. The coil has 4 cm length and 2 cm breadth and is wound for
75 turns. The controlling torque produced for full scale deflection is 55 x 10-° N-m.

(A) 0.4 Whim? (B) 0.183 प्राण
(C) 0.312 Wb/m2 (D) 0.451 Wh/m?

The output voltage of a piezo electric crystal is 240V when it is subjected to a pressure of
2 x 10° N/m?. Calculate its voltage sensitivity if the crystal has a thickness of 3mm.
(A) 25 (B) 0.16
(0 0.04 (D) 28

131/2023 14 A