Electrical Machines The armature core of the rotor bars of dc motors are laminated to reduce eddy current loss. to reduce hysteresis loss. to reduce mechanical losses. to provide better flux linkage. to reduce eddy current loss. to reduce hysteresis loss. to reduce mechanical losses. to provide better flux linkage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 220 V, DC shunt motor is operating at a speed of 1440 rpm. The armature resistance is 1.0 Ω and armature current is 10 A. of the excitation of the machine is reduced by 10%, the extra resistance to be put in the armature circuit to maintain the same speed and torque will be 3.1 Ω 2 .1 Ω 1.8 9 Ω 1.79 Ω 3.1 Ω 2 .1 Ω 1.8 9 Ω 1.79 Ω ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The volt-ampere euation for a long-shunt compound motor is given by Vt= Ea– Iara Vt= Ea + Iara Vt = Ea + Iara+ ILrs Vt = Ea + Ia(ra + rs) Vt= Ea– Iara Vt= Ea + Iara Vt = Ea + Iara+ ILrs Vt = Ea + Ia(ra + rs) ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Generators work on the principle of production of None of these dynamically and statically induced emf. statically induced emf. dynamically induced emf. None of these dynamically and statically induced emf. statically induced emf. dynamically induced emf. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For the purpose of starting an induction motor, star/delta switch is an equivalent to auto transformer of ratio 50% 66.3% 57.7% 33.3% 50% 66.3% 57.7% 33.3% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following machines have highest power factor with respect to magnetizing current? Semi closed slot type machine. Open slot type machines. Closed slot type machines. Any of the above. Semi closed slot type machine. Open slot type machines. Closed slot type machines. Any of the above. ANSWER DOWNLOAD EXAMIANS APP