Electrical Machines If the full load speed of 3-phase, 50Hz induction motor is 950 rpm, what is its half load speed nearly equals to? 940 rpm 975 rpm 1000 rpm 950 rpm 940 rpm 975 rpm 1000 rpm 950 rpm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If in a sub – station there is one 132 / 33 kV transformer whose secondary is connected with primary of one 33 / 11 kV transformer, the total transformation ratio of the sub – station will be, 3. 4. 12. 7. 3. 4. 12. 7. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In case of DC shunt motor if load is reduced The speed will remains almost constant. DC Shunt Motor The speed will increase in proportion to reduction in load. The speed will increase abruptly. The speed will remains almost constant. DC Shunt Motor The speed will increase in proportion to reduction in load. The speed will increase abruptly. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines At what power factor, the voltage regulation of a transformer can be zero ? Zero power factor. Leading power factor. Lagging power factor. Unity power factor. Zero power factor. Leading power factor. Lagging power factor. Unity power factor. 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 air gap. crawling. cogging. relative speed. air gap. crawling. cogging. relative speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 2 pole synchronous machine is operating at 3000 rpm. Find the relation between electrical angular momentum (ωe) and mechanical angular momentum (ωm) ? ωe = 1/2*ωm ωe = ωm ωe = 4*ωm ωe = 2*ωm ωe = 1/2*ωm ωe = ωm ωe = 4*ωm ωe = 2*ωm ANSWER DOWNLOAD EXAMIANS APP