Electrical Machines When applied rated voltage per phase is reduce to one half, the starting torque of three phase squirrel cage induction motor becomes twice the initial value 4 time the initial value 1/4 of the intial value 1/2 of the initial value twice the initial value 4 time the initial value 1/4 of the intial value 1/2 of the initial value ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 6 pole lap connected DC generator with 480 conductors has armature resistance of 0.06 Ω. If the conductors are reconnected to from a wave winding other things remaining unchanged, the value of armature resistance will be 0.06 Ω. 0.54 Ω. 0.54 Ω. 0.01 Ω. 0.06 Ω. 0.54 Ω. 0.54 Ω. 0.01 Ω. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Find the number of poles required, when the frequency is 50Hz and speed of the motor is 500 rpm? 24 5 12 10 24 5 12 10 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 ? 2 alone 1 and 3 1, 2 and 3 1 and 2 2 alone 1 and 3 1, 2 and 3 1 and 2 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A frog leg winding is used in a DC machine to eliminate the use drum winding. reactance voltage produced due to communication. the use of compensating winding. the use equalizer in lap winding. the use drum winding. reactance voltage produced due to communication. the use of compensating winding. the use equalizer in lap winding. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Commutators in DC machines have a role of which converts AC to DC. Both AC to DC and DC to AC. none of these. high voltage DC to low voltage DC. AC to DC. Both AC to DC and DC to AC. none of these. high voltage DC to low voltage DC. ANSWER DOWNLOAD EXAMIANS APP