Electrical Machines A 3 phase stepper motor has 6 stator poles and 4 rotor poles, then find the step angle? 30° 45° 60° 10° 30° 45° 60° 10° ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When R2 is rotor resistance, X2 the rotor reactance at supply frequency and s the slip, then the condition for maximum torque under running condition will be R2 = s2X2. R2 = s2X2. sR2 = X2. R2 = sX2. R2 = s2X2. R2 = s2X2. sR2 = X2. R2 = sX2. 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. How will the machine share, if the load is 600 MW? generator 1 gets over load 230.7 MW and 369.23 MW respectively 200 MW and 400MW respectively generator 2 gets over load generator 1 gets over load 230.7 MW and 369.23 MW respectively 200 MW and 400MW respectively generator 2 gets over load ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which method is less recommendable for induction motor starting in the industries? Auto transformer starting. Stator resistance starting. Direct online starting. Rotor resistance starting. Auto transformer starting. Stator resistance starting. Direct online starting. Rotor resistance starting. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines With the increase in speed of a DC motor 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. both back emf as well as line current increase. back emf increases but line current falls. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements regarding the speed control of dc motors : 1. ward-leonard method is suitable forconstant-torque drives 2. Ward-leonard method is suitable for constant-power drives 3. field-control method facilitates speed control below base speed 4. Armature-resistance control method is more efficient than ward-leanard method 5. Field-control method is suitable for constant-torque drives 6. Armature-resistance control method is suitable for constant-torque drives From these, the correct answer is 1, 2, 5 1, 2, 6 1, 3, 5 1, 4, 6 1, 2, 5 1, 2, 6 1, 3, 5 1, 4, 6 ANSWER DOWNLOAD EXAMIANS APP