Electrical Machines A commutator with a diameter of 50 cm rotating at 1000 rpm. For a brush width of 1.5 cm, find the time of commutation in ms. 0.512. 0.443. 0.573. 0.649. 0.512. 0.443. 0.573. 0.649. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An unexcited single phase synchronous motor is reluctance motor. universal motor. AC series motor. repulsion motor. reluctance motor. universal motor. AC series motor. repulsion motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The direction of rotation of conductor of a DC motor can be determined by Ampere law. Fleming's left hand rule. Lenz's law. Fleming's right hand rule. Ampere law. Fleming's left hand rule. Lenz's law. Fleming's right hand rule. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of following methods are suitable for the speed control of squirrel cage induction motor? 1. Voltage control. 2. Frequency control. 3. Pole changing method. 4. Rotor resistance control select the correct answer using the codes given below:- 1, 3 and 4. 2 and 4. 2, 3 and 4. 1, 2 and 3. 1, 3 and 4. 2 and 4. 2, 3 and 4. 1, 2 and 3. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a synchronous machine, if the field flux axis is ahead of the armature field axis in the direction of rotation, the machine operating is synchronous generator. synchronous motor. asynchronous generator. asynchronous motor. synchronous generator. synchronous motor. asynchronous generator. asynchronous motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines DC generator will not build up voltage if it has lost residual magnetism. any one of above. if field resistance is more than critical resistance. due to wrong direction of rotation. if it has lost residual magnetism. any one of above. if field resistance is more than critical resistance. due to wrong direction of rotation. ANSWER DOWNLOAD EXAMIANS APP