Electrical Machines If s is the slip and f is the supply frequency of an induction motor, the frequency of rotor current is given by s2. sf / 2. f / s. sf. s2. sf / 2. f / s. sf. 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 2 .1 Ω 3.1 Ω 1.79 Ω 1.8 9 Ω 2 .1 Ω 3.1 Ω 1.79 Ω 1.8 9 Ω ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines With the increase in speed of a DC motor back emf increases but line current falls. both back emf as well as line current increase. both back emf as well as line current fall. back emf falls and line current increases. back emf increases but line current falls. both back emf as well as line current increase. both back emf as well as line current fall. back emf falls and line current increases. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of following motor is preferred for belt conveyor? Slip ring induction motor. Synchronous motors. Universal motor. Reluctance motor. Slip ring induction motor. Synchronous motors. Universal motor. Reluctance motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Cogging and crawling are phenomena associated with cage induction machines and they are essentially the same. any of the above. the former at a fraction of its rate speed and the latter during starting. the former during starting and the latter at a fraction of its rated speed. cage induction machines and they are essentially the same. any of the above. the former at a fraction of its rate speed and the latter during starting. the former during starting and the latter at a fraction of its rated speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For higher values of armature, the speed of a DC series motor is Inversely proportional to armature current. Proportional to the square of armature current. Constant. Proportional to armature current. Inversely proportional to armature current. Proportional to the square of armature current. Constant. Proportional to armature current. ANSWER DOWNLOAD EXAMIANS APP
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