Electrical Machines A transformer has hysteresis loss of 30 W, at 240 V, 60 Hz. The hysteresis loss at 200 V, 50 Hz will be 28 W. 30 W. 25 W. 36 W. 28 W. 30 W. 25 W. 36 W. 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. Draw too much current. Produce sparking at brushes. Open fuse or circuit breaker. Develop excessive speed and damage itself. Draw too much current. Produce sparking at brushes. Open fuse or circuit breaker. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When maximum flux density is constant, the eddy current losses are proportional to V f f2 V2 V f f2 V2 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following DC motors has got maximum relieving property? Differentical compound. Series. Shunt. Cummulative compound. Differentical compound. Series. Shunt. Cummulative compound. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The speed of a 3-phase induction motor operating in its stable region decreases with increase in the load torque. remains constant. increases with increase in the load torque. decreases with decrease in the load torque. decreases with increase in the load torque. remains constant. increases with increase in the load torque. decreases with decrease in the load torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 220 V, DC shunt motor is operating at a speed of 1440 rpm. The armature resistance is 1.0 Ω and armature current is 10 A. of the excitation of the machine is reduced by 10%, the extra resistance to be put in the armature circuit to maintain the same speed and torque will be 2 .1 Ω 1.8 9 Ω 3.1 Ω 1.79 Ω 2 .1 Ω 1.8 9 Ω 3.1 Ω 1.79 Ω ANSWER DOWNLOAD EXAMIANS APP