Electrical Machines The current drawn by a 220 V DC series motor of armature resistance 0.5Ω and back back emf 200 V is 440 A. 400 A. 44 A. 40 A. 440 A. 400 A. 44 A. 40 A. 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 1.79 Ω 1.8 9 Ω 2 .1 Ω 3.1 Ω 1.79 Ω 1.8 9 Ω 2 .1 Ω 3.1 Ω ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The shaft torque of a dc motor is less than the electromagnetic torque because of hysteresis losses. eddy current losses. mechanical losses. ohmic losses. hysteresis losses. eddy current losses. mechanical losses. ohmic losses. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following is/are effects of armature reaction? increase the iron loss All of these increases the design cost increase the maintenance and repair increase the iron loss All of these increases the design cost increase the maintenance and repair ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When Flemings right hand rule to find the direction of induced emf, the thumb points towards direction of induced emf. opposite to the direction of motion of the conductor. direction of motion of the conductor. direction of flux. direction of induced emf. opposite to the direction of motion of the conductor. direction of motion of the conductor. direction of flux. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The frequency of voltage generated by an alternator having 8 poles and rotating at 250 rpm is 16.67 Hz. 60 Hz. 50 Hz. 25 Hz. 16.67 Hz. 60 Hz. 50 Hz. 25 Hz. ANSWER DOWNLOAD EXAMIANS APP