Electrical Machines If the armature electric current is increased to double its previous value, and the time of commutation is halved, how will the reactance voltage vary? It will becomes four times. It will be halved. It will remain the same. It will be doubled. It will becomes four times. It will be halved. It will remain the same. It will be doubled. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A simple method of increasing the voltage of a DC generator is to increase the speed of shaft rotation. increase the number of turns in armature coil. increase the number of turns in field coil. increase the source frequency. increase the speed of shaft rotation. increase the number of turns in armature coil. increase the number of turns in field coil. increase the source frequency. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC generators, the brushes remain in contact with conductors which lie in the inter polar gaps. lie under north pole. lie under south pole. there is no hard and fast rule for this. lie in the inter polar gaps. lie under north pole. lie under south pole. there is no hard and fast rule for this. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the field winding connection of DC shunt motor is changed It will run in opposite direction. It will run in same direction. motor will not run. motor will become slow. It will run in opposite direction. It will run in same direction. motor will not run. motor will become slow. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For power factor improvement the synchronous motor is to be heavily loaded and over excited lightly loaded and underecited lightly loaded and over excited heavily loaded and underexcited heavily loaded and over excited lightly loaded and underecited lightly loaded and over excited heavily loaded and underexcited ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements : Interpoles in dc machines 1. reducearmature reaction effects in the interpolar region 2. have the same dimension as main polls 3. have their windings connected in series with the armature 4. have same number of turns as the armature 5. have the polarity same as that of the main pole ahead in a motor From these, the correct statements are 1, 2 and 3 1 and 3 1, 2, 3 and 5 1, 3 and 5 1, 2 and 3 1 and 3 1, 2, 3 and 5 1, 3 and 5 ANSWER DOWNLOAD EXAMIANS APP