DGVCL Exam Paper (11-12-2011) At time t= 0+ , with zero initial condition, which of the following acts as a short circuit? Conductor Capacitor Voltage source Resistor Conductor Capacitor Voltage source Resistor ANSWER DOWNLOAD EXAMIANS APP
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 More than 90% Less than 90% 80 % 90 % More than 90% Less than 90% 80 % 90 % 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) Two parallel conductors are carrying the current in the same direction. Which of the following statements is correct? There is a repelling force between the conductors The force increases when the distance between the conductors is increased The force increases when the distance between the conductors is decreased There is an attracting force between the conductors There is a repelling force between the conductors The force increases when the distance between the conductors is increased The force increases when the distance between the conductors is decreased There is an attracting force between the conductors ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) What type of insulator is used if the direction of the transmission line is to be changed? Strain type Pin type Shakle type Suspebsion type Strain type Pin type Shakle type Suspebsion type ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) Permittivity is expressed in terms of N/m Farad/m farad/sq. m. Weber /m N/m Farad/m farad/sq. m. Weber /m ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) In the protection of transformers, harmonic restraint is used to guard against Magnetizing inrush current Lightning Switching over voltages Unbalanced protection Magnetizing inrush current Lightning Switching over voltages Unbalanced protection ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Initial inrush of magnetizing currents have high component of even and odd harmonics.2nd - 63%3rd -26.8%4th- 5.1%5th- 4.1%6th- 3.77th-2.4