Electrical Machines A 4 pole lap wound dc generator has 4 brushes, if one of the brush is damaged, what will be the change in V, I and P ratings V, I and P V/2, I/2 and P/4 V, I/2 and P/2 V/2, I and P/2 V, I and P V/2, I/2 and P/4 V, I/2 and P/2 V/2, I and P/2 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The squirrel cage induction motors are provided with blades in order to facilitate cooling of rotor. none of these. eliminate noise. balance the rotor dynamically. facilitate cooling of rotor. none of these. eliminate noise. balance the rotor dynamically. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The use of higher flux density in the transformer design increases the weigh per KVA reduces the weigh per KVA None of these has no relation with the weight of transformer increases the weigh per KVA reduces the weigh per KVA None of these has no relation with the weight of transformer ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements regarding dc machines : 1. possible resistance of shunt-field winding is 1 Ω 2. possible resistance of series-field winding is 1 Ω 3. electrographite brushes are used for 230 V, 10 A machines 4. Copper-graphite brushes are used for 230 V, 10 A machines 5. Possible armature-circuit resistance is 1 Ω From these, the correct statements are 2, 4 ,5 1, 3, 5 2, 3 , 5 1, 4 2, 4 ,5 1, 3, 5 2, 3 , 5 1, 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following load normally needs starting torque more than rated torque? Conveyers. Air compressors. Blowers. Centrifugal pumps. Conveyers. Air compressors. Blowers. Centrifugal pumps. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines With the increase in speed of a DC motor both back emf as well as line current increase. back emf increases but line current falls. back emf falls and line current increases. both back emf as well as line current fall. both back emf as well as line current increase. back emf increases but line current falls. back emf falls and line current increases. both back emf as well as line current fall. ANSWER DOWNLOAD EXAMIANS APP