DGVCL Exam Paper (11-12-2011) DC series motors are best suited for traction work because Its torque is proportional to the square of the armature current and speed is directional proporational to torque Its torque is proportional to the square of the armature current and speed is inversely proportional 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 directional proporational to torque Its torque is proportional to the square of the armature current and speed is inversely proportional 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 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) An over excited synchronous motor draws current at Depends on nature of load Lagging power factor Unity power factor Leading power factor Depends on nature of load Lagging power factor Unity power factor Leading power factor ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Over excitation : leading currentUnder excitation : lagging currentNormal excitation : current with unity PF (in phase current)
DGVCL Exam Paper (11-12-2011) Which of the following power distribution system gives better reliabity ? None of these DC 3 wire system Ring main system Radial system None of these DC 3 wire system Ring main system Radial system ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) Reactance relay is used to protect against Phase faults only Over voltage faults Both phase and earth faults Earth faults only Phase faults only Over voltage faults Both phase and earth faults Earth faults only ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) What happens to the contents of RAM (Random Access Memory) when the power of the computer is turned off? Content is lost Content gets corrupted Content is transferred to other memory Content remains intact Content is lost Content gets corrupted Content is transferred to other memory Content remains intact ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) If the percentage reactance of the system upto the point of fault is 20% and the base kVA is 10,000 the short ciruit kVA is 10 MVA 50 MVA 20 MVA 60 MVA 10 MVA 50 MVA 20 MVA 60 MVA ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Short circuit kVA = Base kVA/%X
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