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. 0.649. 0.443. 0.512. 0.573. 0.649. 0.443. 0.512. 0.573. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following represents the rotating losses of machine? Hysteresis losses Friction and windage losses All of the them Eddy current losses Hysteresis losses Friction and windage losses All of the them Eddy current losses ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the number of rotor slots is equal to number of stator slots, then motor refuses to start. Hence it is known as relative speed. crawling. cogging. air gap. relative speed. crawling. cogging. air gap. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A smaller air gap in a induction motor helps to reduce the chance of crawling. reduce the magnetizing current. reduce the chance of cogging. increase the starting torque. reduce the chance of crawling. reduce the magnetizing current. reduce the chance of cogging. increase the starting torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 100/10, 50 VA double winding transformer is converted to 100/110 V auto transformer. The rating of auto transformer is 500 VA 110 VA 100 VA 550 VA 500 VA 110 VA 100 VA 550 VA ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature core of a DC machine is laminated to minimise mechanical loss eddy-current loss temperature rise hysteresis loss mechanical loss eddy-current loss temperature rise hysteresis loss ANSWER DOWNLOAD EXAMIANS APP