Electrical Machines With the increase in speed of a DC motor both back emf as well as line current increase. back emf increases but line current falls. both back emf as well as line current fall. back emf falls and line current increases. both back emf as well as line current increase. back emf increases but line current falls. both back emf as well as line current fall. back emf falls and line current increases. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC generator sparking between brushes and commutator surface may be due to under commutation. too rapid reversal of current. any of the above. over commutation. under commutation. too rapid reversal of current. any of the above. over commutation. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the applied voltage of a DC motor is 230 V, then back emf, for maximum power developed is 115 V. 230 V. 460 V. 200 V. 115 V. 230 V. 460 V. 200 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Shunt field of DC generators consists of--------number of turns and ---------- conductors respectively less and thin large and thick large and thin less and thick less and thin large and thick large and thin less and thick ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Transformer action requires a alternating magnetic lux. constant magnetic flux. increasing magnetic flux. alternating electric flux. alternating magnetic lux. constant magnetic flux. increasing magnetic flux. alternating electric flux. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Poles of DC machine are often laminated to reduce iron weight. dissipate more heat. reduce armature reaction. reduce pulsation loss. reduce iron weight. dissipate more heat. reduce armature reaction. reduce pulsation loss. ANSWER DOWNLOAD EXAMIANS APP