Electrical Machines In a loaded DC motor, if the brushes are given a shift from the interpolar axis in the direction of rotation, then the commutation will deteriorate and the speed falls. improve and the speed falls. improve and the speed rises. deteriorate and the speed rises. deteriorate and the speed falls. improve and the speed falls. improve and the speed rises. deteriorate and the speed rises. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following machine is invariably provided with forced ventilation? Fractional horse power high speed motor. Hermetically sealed motor of refrigerator. Fractional horse power slow speed motor. 50 MW generator in a power plant. Fractional horse power high speed motor. Hermetically sealed motor of refrigerator. Fractional horse power slow speed motor. 50 MW generator in a power plant. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A large series motor is never started without some mechanical on it because otherwise it will Open fuse or circuit breaker. Draw too much current. Produce sparking at brushes. Develop excessive speed and damage itself. Open fuse or circuit breaker. Draw too much current. Produce sparking at brushes. Develop excessive speed and damage itself. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The synchronous speed of an induction motor will be increased by decreasing of frequency. speed can not be increased. increasing of frequency. increasing number of poles. decreasing of frequency. speed can not be increased. increasing of frequency. increasing number of poles. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Sparkless commutation can be achieved by employing any one or more of the above methods. compensating winding. high resistance carbon brushes. inter poles. any one or more of the above methods. compensating winding. high resistance carbon brushes. inter poles. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the source voltage of a DC motor is increased, which of the following will decrease? Starting torque, operating speed, full load current. Operating speed. Starting torque. Full load current. Starting torque, operating speed, full load current. Operating speed. Starting torque. Full load current. ANSWER DOWNLOAD EXAMIANS APP
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