Electrical Machines In DC motors, under trailing pole tips, flux density will_______ ? either increase or decrease decrease increase None of these either increase or decrease decrease increase None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature core of the rotor bars of dc motors are laminated to reduce mechanical losses. to reduce eddy current loss. to provide better flux linkage. to reduce hysteresis loss. to reduce mechanical losses. to reduce eddy current loss. to provide better flux linkage. to reduce hysteresis loss. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3 - Φ, 6 pole, 50 Hz IM has a rotor speed of 987 rpm find rotor frequency? 0.75 Hz. 0.65 Hz. 60 Hz. 0.70 Hz. 0.75 Hz. 0.65 Hz. 60 Hz. 0.70 Hz. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A simple method of increasing the voltage of a DC generator is to increase the number of turns in field coil. increase the speed of shaft rotation. increase the number of turns in armature coil. increase the source frequency. increase the number of turns in field coil. increase the speed of shaft rotation. increase the number of turns in armature coil. increase the source frequency. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The following statements relate to compensating winding (CW) and interpole winding (IW) of a dc machine : 1. CW neutralizes the armature reaction under a pole pitch 2. IW is connected in series with armature circuit 3. IW produces mmf in the commutating zone only 4. CWmmf is directed along the brush axis 5. Mmf produced by IW is equal to armature mmf From these, the correct statements are 1, 3, 4, 5 2, 3, 4, 5 1, 2, 3, 4 and 5 2, 3, 4 1, 3, 4, 5 2, 3, 4, 5 1, 2, 3, 4 and 5 2, 3, 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Cogging in induction motor occurs when number of stator teeth - number of rotor teeth = 0. number of stator teeth - number of rotor teeth = negative number. number of stator teeth - number of rotor teeth = odd number. number of stator teeth - number of rotor teeth = even number. number of stator teeth - number of rotor teeth = 0. number of stator teeth - number of rotor teeth = negative number. number of stator teeth - number of rotor teeth = odd number. number of stator teeth - number of rotor teeth = even number. ANSWER DOWNLOAD EXAMIANS APP