Electrical Machines What is the mechanical power developed by a DC series motor is maximum? Back emf is equal to half the applied voltage. Back emf is equal to zero. Back emf is equal to applied voltage. None of above. Back emf is equal to half the applied voltage. Back emf is equal to zero. Back emf is equal to applied voltage. None of above. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC series motor drawing an armature current of Ia is operating under saturated magnetic conditions. The torque developed in the motor is proportional to 1/Ia Ia2 I/Ia2 Ia 1/Ia Ia2 I/Ia2 Ia ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When two DC series motors are connected in parallel, the resultant speed is less than normal speed. more than normal speed. zero. normal speed. less than normal speed. more than normal speed. zero. normal speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Sparkless commutation can be achieved by employing any one or more of the above methods. high resistance carbon brushes. inter poles. compensating winding. any one or more of the above methods. high resistance carbon brushes. inter poles. compensating winding. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A commutator in DC machines can 1. provide half-wave rectification 2. Provide full-wave rectification 3. convert ac to dc 4. Convert dc to ac 5. provide controlled full-wave rectification From these, the correct answer is 2, 3 ,5 2, 3, 4 2, 3, 4, 5 1, 2, 3 2, 3 ,5 2, 3, 4 2, 3, 4, 5 1, 2, 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An auto transformer having a transformation ratio of 0.8 supplies a load pf 10 KW. The power transfered inductively from the primary to secondary is 8 KW. 2 KW. 10 KW. 0. 8 KW. 2 KW. 10 KW. 0. ANSWER DOWNLOAD EXAMIANS APP
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