Electrical Machines The back emf produced in a dc motor depends on P. P and Z. Z. none of these. P. P and Z. Z. none of these. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements : For a level compounded dc generator to run at constant voltage, the series field mmf must effectively compensate 1. armature reaction mmf 2.armature resistance drop 3. brush contact voltage drop Which of these statements is/are correct ? 1, 2 and 3 1 and 2 2 alone 1 and 3 1, 2 and 3 1 and 2 2 alone 1 and 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a three phase slip-ring induction motor, brushes are connected to DC supply. equalizing coils. external star-connected resistors. 3 - Φ AC supply. DC supply. equalizing coils. external star-connected resistors. 3 - Φ AC supply. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a 3 - Φ IM in order to eliminate cogging the number of stator slots must be an integral multiple of number of rotor slots. equal to number of rotor slots. either (B) or (C). unequal to number of rotor slots and skewed in shape. an integral multiple of number of rotor slots. equal to number of rotor slots. either (B) or (C). unequal to number of rotor slots and skewed in shape. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Two synchronous generators operating in parallel 200 MW and 400 MW respectively. The drooping characteristics of their governors are identical as 4% from no load to full load. Consider the governors operating at 50Hz on no load. What is the operating frequency, if the load is 600 MW? 45 HZ 50 Hz 48.5 Hz 48 Hz 45 HZ 50 Hz 48.5 Hz 48 Hz ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A single phase transformer has specifications as 250 KVA, 11000 V/415 V, 50 Hz. What are the values of primary and secondary currents? primary = 602 A, secondary = 22.7 A primary = 11.4 A, secondary = 301 A primary = 22.7 A, secondary = 602.4 A primary = 301 A, secondary = 22.7 A primary = 602 A, secondary = 22.7 A primary = 11.4 A, secondary = 301 A primary = 22.7 A, secondary = 602.4 A primary = 301 A, secondary = 22.7 A ANSWER DOWNLOAD EXAMIANS APP