DGVCL Exam Paper (11-12-2011) At time t= 0+ , with zero initial condition, which of the following acts as a short circuit? Capacitor Conductor Voltage source Resistor Capacitor Conductor Voltage source Resistor ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) It is difficult interrupt a capacitive current because Stored energy in the capacitor is very high Current magnitude is very small It has a leading power factor The restriking voltage can be high Stored energy in the capacitor is very high Current magnitude is very small It has a leading power factor The restriking voltage can be high ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) Ybus used in power flow studies and Zbus used in short circuit studies Are the same Are transpose of each other Are inverse of each other Have no inter relation Are the same Are transpose of each other Are inverse of each other Have no inter relation ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) DC series motors are best suited for traction work because Torque and speed are proportional to the square of the armature current Torque and speed are inversely proportional to the square of the armature current Its torque is proportional to the square of the armature current and speed is inversely proportional to torque Its torque is proportional to the square of the armature current and speed is directional proporational to torque Torque and speed are proportional to the square of the armature current Torque and speed are inversely proportional to the square of the armature current Its torque is proportional to the square of the armature current and speed is inversely proportional to torque Its torque is proportional to the square of the armature current and speed is directional proporational to torque ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Torque in d.c motor = k* φ * IaIn series motor φ α IaTα I²N α 1/φN α 1/T
DGVCL Exam Paper (11-12-2011) The mutual inductance between two unity coupled coils of 9 H and 4 H is 36 H 2.2 H 13 H 6 H 36 H 2.2 H 13 H 6 H ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) A 3 phase, 6 pole induction motor operates on 440 V, 50 Hz, supply. If the actual speed of the motor is 960 rpm the slip will be 6 % 0.4 % 4 % 5 % 6 % 0.4 % 4 % 5 % ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Ns = 120f/PSlip=(Ns-Nr)/NsNs = 1000 and Nr = 960 from equation of slip, S = (1000-960)/1000S = 0.04 or 4%
EXAMIANS