DGVCL Exam Paper (11-12-2011) It is difficult interrupt a capacitive current because Current magnitude is very small Stored energy in the capacitor is very high It has a leading power factor The restriking voltage can be high Current magnitude is very small Stored energy in the capacitor is very high It has a leading power factor The restriking voltage can be high ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) Permittivity is expressed in terms of Weber /m Farad/m N/m farad/sq. m. Weber /m Farad/m N/m farad/sq. m. 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) 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 80 % 90 % More than 90% Less than 90% 80 % 90 % More than 90% Less than 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) The purpose of providing a choke in a tube light is To avoid radio interference To eliminate corona effect To improve the power factor To limit the current to an appropriate value To avoid radio interference To eliminate corona effect To improve the power factor To limit the current to an appropriate value ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) The transient stability of a power system can be improved by Increasing the turbine valve opening Phase shifting transformer Excitation control Single pole switching of circuit breakers Increasing the turbine valve opening Phase shifting transformer Excitation control Single pole switching of circuit breakers ANSWER DOWNLOAD EXAMIANS APP
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