Electrical Machines In a DC generator, if P be the number of poles and N be the rpm of the rotor, then frequency of magnetic reversals will be PN/120. PN/60. PN/3000. PN/2. PN/120. PN/60. PN/3000. PN/2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A smaller air gap in a polyphase induction motor helps to reduce the chance of crawling. reduce the magnetizing current. reduce the chance of cogging. increase the starting torque. reduce the chance of crawling. reduce the magnetizing current. reduce the chance of cogging. increase the starting torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Resistance commutation is used generally in case of fractional kW DC machines. None of these DC machines bellow 5 kW. DC machines above 10 kW. fractional kW DC machines. None of these DC machines bellow 5 kW. DC machines above 10 kW. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Find the synchronous reactance of alternators in which a given field current of 200 A on short circuit and a generated emf of 50 V on open circuit. Armature resistance is 0.1 ohm 0.25Ω. 1Ω. 0.23Ω. 0.5Ω. 0.25Ω. 1Ω. 0.23Ω. 0.5Ω. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the number of rotor slots is equal to number of stator slots, then motor refuses to start. Hence it is known as air gap. crawling. relative speed. cogging. air gap. crawling. relative speed. cogging. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Skewing of cage rotors offers the following advantages all of below. less noise. locking tendency is reduced. uniform torque. all of below. less noise. locking tendency is reduced. uniform torque. ANSWER DOWNLOAD EXAMIANS APP