Electrical Machines As compared to an induction motor, the air gap in a DC motor is less than 50%. more. between 50% and 90%. same. less than 50%. more. between 50% and 90%. same. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 230 V, 50 Hz, 4 pole single phase induction motor is rotating in the clockwise ( forward ) direction at a speed of 1425 rpm. If the rotor resistance at standstill is 7.8 Ω. Then the effective rotor resistance in the backward branch of the equivalent circuit will be 4 Ω. 2 Ω. 8 Ω. 10 Ω. 4 Ω. 2 Ω. 8 Ω. 10 Ω. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What happens if fifth multiples of harmonics is given to induction motor? It will rotates in reverse direction. Fail to start. Either short circuit or open circuit occurs. It will rotates in normal operation. It will rotates in reverse direction. Fail to start. Either short circuit or open circuit occurs. It will rotates in normal operation. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Motors for fans and pumps are selected in the rpm range 375 to 500. 500 to 720. 1440 to 2880. 720 to 920. 375 to 500. 500 to 720. 1440 to 2880. 720 to 920. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a dc machine, 1. physically, the brush axis is along the direct axis 2. physically, the brush axis is along the interpolar axis 3. schematically, the brush axis is along the direct axis 4. schematically, the brush axis is along the quadrature axis 5. armaturemmf is directed along the brush axis From these, the correct statements are 1 , 3, 5 1, 4,5 2, 3, 5 2, 4, 5 1 , 3, 5 1, 4,5 2, 3, 5 2, 4, 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Commutators in DC machines have a role of which converts high voltage DC to low voltage DC. Both AC to DC and DC to AC. AC to DC. none of these. high voltage DC to low voltage DC. Both AC to DC and DC to AC. AC to DC. none of these. ANSWER DOWNLOAD EXAMIANS APP