DGVCL Exam Paper (11-12-2011) Due to skin effect Portion of the conductor near the surface carries more current and the core of the conductor carries less current Uniform current flows through the conductor Current flows through the half cross section of the conductor Portion of the conductor near the surface carries less current and the core of the conductor carries more current Portion of the conductor near the surface carries more current and the core of the conductor carries less current Uniform current flows through the conductor Current flows through the half cross section of the conductor Portion of the conductor near the surface carries less current and the core of the conductor carries more current ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Skin Effect:tendency of the current to crowd near the conductor surface.Skin effect is proportional to frequency, conductor diameter and permiability. Skin effect increases effective resistance of conductor.In DC, no skin effect.
DGVCL Exam Paper (11-12-2011) DC series motors are best suited for traction work because Torque and speed are inversely proportional to the square of the armature current Torque and speed are 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 inversely proportional to the square of the armature current Torque and speed are 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 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) 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 decreased There is an attracting force between the conductors The force increases when the distance between the conductors is increased There is a repelling force between the conductors The force increases when the distance between the conductors is decreased There is an attracting force between the conductors The force increases when the distance between the conductors is increased ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) The circuit breaker generally used in railway traction is Bulk Oil CB Vacuum CB Minimum Oil CB Air break CB Bulk Oil CB Vacuum CB Minimum Oil CB Air break CB ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) A Mho relay is a Directional restrained over voltage relay Voltage restrained directional relay Voltage controlled over current relay Directional restrained over current relay Directional restrained over voltage relay Voltage restrained directional relay Voltage controlled over current relay Directional restrained over current relay ANSWER DOWNLOAD EXAMIANS APP
DGVCL Exam Paper (11-12-2011) The picture on the monitor of a computer is made up of tiny coloured dots called Points Icons Pixels Spots Points Icons Pixels Spots ANSWER DOWNLOAD EXAMIANS APP