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 % Less than 90% More than 90% 90 % 80 % Less than 90% More than 90% 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) Permittivity is expressed in terms of Farad/m N/m farad/sq. m. Weber /m Farad/m N/m farad/sq. m. Weber /m ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) The advantage of slipring induction motor over the squirrel cage induction motor is It has a higher efficiency It is suitable for higher speeds It's power factor is higher It can be started with the help of rotor resistances It has a higher efficiency It is suitable for higher speeds It's power factor is higher It can be started with the help of rotor resistances ANSWER EXPLANATION DOWNLOAD EXAMIANS APP slip ring motor have high starting torque compare to squirrel cage motor and have good speed controlalso have high over loading capacity, smooth acceleration under heavy loads.
DGVCL Exam Paper (11-12-2011) A fuse is inserted in Earth continuity conductor Both phased and neutral wire Neutral wire Phase wire Earth continuity conductor Both phased and neutral wire Neutral wire Phase wire ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) Different computers are connected to a LAN by a cable and a Telephone line Modem Interface card Special wires Telephone line Modem Interface card Special wires ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) If the excitation of a synchronous generator fails, it acts as a Synchronous motor Induction motor Synchronous generator Induction generator Synchronous motor Induction motor Synchronous generator Induction generator ANSWER EXPLANATION DOWNLOAD EXAMIANS APP if excitation of synchronous generator fails, operate as induction motor