DGVCL Exam Paper (11-12-2011) In a series RLC circuit at resonance Current is minimum and power factor is unity Current is maximum and power factor is 0.5 Current is maximum and power factor is unity Current is minimum and power factor is 0.5 Current is minimum and power factor is unity Current is maximum and power factor is 0.5 Current is maximum and power factor is unity Current is minimum and power factor is 0.5 ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) In which of the following motors, the stator and rotor magnetic fields rotate at the same speed? Induction motor Universal motor Reluctance motor Synchronous motor Induction motor Universal motor Reluctance motor Synchronous motor ANSWER EXPLANATION DOWNLOAD EXAMIANS APP In all machine stator and rotor magnetic field rotates (stationary with respect to each other) at synchronous speed with respect to stationary observer.
DGVCL Exam Paper (11-12-2011) Which motor is used to start heavy loads? Shunt motor Cumulatively compounded motor Differentially compounded motor Series motor Shunt motor Cumulatively compounded motor Differentially compounded motor Series motor ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Torque in d.c motor = k* φ * IaIn series motor φ α IaTα I²starting torque of dc series motor is high
DGVCL Exam Paper (11-12-2011) The efficiency of a transformer at full load, 0.8 p.f. lag is 90%. Its efficiency at full load, 0.8 p.f. lead will be Less than 90% 90 % More than 90% 80 % Less than 90% 90 % More than 90% 80 % ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Efficiency= output power/input powerefficiency = (v*i*cosφ)/((v*i*cosφ)+(x² Pc)+(Pi)) x=fractional part of full load
DGVCL Exam Paper (11-12-2011) The bus bar zone faults are generally Three phase short ciruits Double line to ground faults Phase to phase faults Single line to ground faults Three phase short ciruits Double line to ground faults Phase to phase faults Single line to ground faults ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) People can interact with each other through any part of the world through video conferencing using Scanner Joystick Webcam Speaker Scanner Joystick Webcam Speaker ANSWER DOWNLOAD EXAMIANS APP