Electrical Machines In case the conditions for maximum power for DC motor are established, the efficiency of the motor will be Around 100 %. Any where between 75 % and 90 %. Less than 50 % Around 90 % Around 100 %. Any where between 75 % and 90 %. Less than 50 % Around 90 % ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When a synchronous motor is running at synchronous speed, the damper winding produces no torque. damping torqe. eddy current torque. both 1 and 2. no torque. damping torqe. eddy current torque. both 1 and 2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines During no load test, an induction motor draws power only for the small copper loss. for core loss and windage and friction loss. for copper loss and windage friction loss. for core loss and copper loss. only for the small copper loss. for core loss and windage and friction loss. for copper loss and windage friction loss. for core loss and copper loss. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If an AC servomotor has one of its winding excited by AC, then voltage measured at the other winding with rotor running will be constant independent of speed. zero. proportional to rotor speed. proportional to square of rotor speed. constant independent of speed. zero. proportional to rotor speed. proportional to square of rotor speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A transformer core is made up of a silicon steel laminations which has maximum flux density 1 Tesla. If it was cold rolled grain oriented its flux density increases to 1.6 Tesla. What is the saving in core size or area due to cold rolled grain oriented process? 60% 68% 40% 38% 60% 68% 40% 38% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Two dc machines A and B, using the same conductor material, have armature circuit resistances of 0.4 Ω and 1.2 Ω respectively. Of the two machines, A is bigger than B for the same current rating A is bigger than B for the same voltage rating both are of the same size for the same current rating B is bigger than A for the same current rating A is bigger than B for the same current rating A is bigger than B for the same voltage rating both are of the same size for the same current rating B is bigger than A for the same current rating ANSWER DOWNLOAD EXAMIANS APP