Electrical Machines In a DC shunt generator working on load, the brushes are moved forward in the direction of rotation, as a result of this, commutation will improve and terminal voltage will rise . improve but terminal voltage will fall. worsen and terminal voltage will rise. worsen and terminal voltage will fall improve and terminal voltage will rise . improve but terminal voltage will fall. worsen and terminal voltage will rise. worsen and terminal voltage will fall ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a 3 - Φ IM with line frequency f1 and winding factor kw1 and kw2 for stator and rotor respectively the ratio of per phase stator winding emf E1 to per phase rotor winding emf E2 at standstill is given by E1 / E2 = f1kw1 / f2kw2. E1 / E2 = N1kw1 / N2kw2. E1 / E2 = 1. E1 / E2 = N1 / N2. E1 / E2 = f1kw1 / f2kw2. E1 / E2 = N1kw1 / N2kw2. E1 / E2 = 1. E1 / E2 = N1 / N2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A transformer has maximum efficiency at 3/4 load. The ratio of iron loss and full load copper loss is 4/3. 3/4. 9/16. 16/9. 4/3. 3/4. 9/16. 16/9. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 400 V, 50 Hz, 30 Hp, three phase IM is drawing 50 A current at 0.8 p.f lagging. The stator and rotor copper losses are 1.5 KW and 900 W respectively. The friction and windage losses are 1050 W and core losses are 1200 W. The air gap power of the motor will be 26.21 kW. 24.11 kW. 25 kW. 23.06 kW. 26.21 kW. 24.11 kW. 25 kW. 23.06 kW. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The 3 - Φ induction motors are, by a very considerable margin, the most widely used AC motors as they have maximum efficiency and maximum starting torque. these are cheaper in cost, simple and rugged in construction. they are capable of operation under range of leading and lagging pf. they have very good speed regulation. they have maximum efficiency and maximum starting torque. these are cheaper in cost, simple and rugged in construction. they are capable of operation under range of leading and lagging pf. they have very good speed regulation. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a seperately excited DC Motor if field current is increased, it will Reduce armature heating. Increase acceleration duration. Increase speed Reduce starting torque. Reduce armature heating. Increase acceleration duration. Increase speed Reduce starting torque. ANSWER DOWNLOAD EXAMIANS APP
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