Electrical Machines A transformer has maximum efficiency at 3/4 load. The ratio of iron loss and full load copper loss is 16/9. 9/16. 4/3. 3/4. 16/9. 9/16. 4/3. 3/4. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The rotor speed of an induction motor is given by Ns = 120f /p × ( 1 - r). Ns = 120f / p × ( 1 - s ). None of these Nr = 120f / p × (1-s). Ns = 120f /p × ( 1 - r). Ns = 120f / p × ( 1 - s ). None of these Nr = 120f / p × (1-s). ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In diesel engine, gas engine type of machine contains ___________________ pole type of alternator. non uniform cylindrical. none of these. cylindrical. salient. non uniform cylindrical. none of these. cylindrical. salient. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the field winding connection of DC shunt motor is changed motor will not run. It will run in same direction. motor will become slow. It will run in opposite direction. motor will not run. It will run in same direction. motor will become slow. It will run in opposite direction. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A large series motor is never started without some mechanical on it because otherwise it will 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. Open fuse or circuit breaker. Draw too much current. Produce sparking at brushes. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 240 V, dc shunt motor draws 15 A while supplying the rated load at a speed of 80 rad/s. The armature resistance is 0.5 W and the field winding resistance is 80 W. The external resistance to be added in the armature circuit to limit the armature current to 125% of its rated value is 31.9 Ω 31.1 Ω 15.1 Ω 15.9 Ω 31.9 Ω 31.1 Ω 15.1 Ω 15.9 Ω ANSWER DOWNLOAD EXAMIANS APP