Electrical Machines A commutator with a diameter of 50 cm rotating at 1000 rpm. For a brush width of 1.5 cm, find the time of commutation in ms. 0.573. 0.512. 0.649. 0.443. 0.573. 0.512. 0.649. 0.443. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In most condition which frame of motor will be preferred? Splash proof. Totally enclosed fan coiled. Drip proof. Open type. Splash proof. Totally enclosed fan coiled. Drip proof. Open type. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3-φ alternator has negligible stator resistance. A short circuit test is conducted on this alternator. At a particular speed, a field current of If1 is required to drive the rated armature current. If the speed of the alternator is reduced to half, the field current required to maintain rated armature current Woud be equal to 2If1. Cannot be predicted due to insufficient data. Would be equal to If1. Would be equal to If1/2. Woud be equal to 2If1. Cannot be predicted due to insufficient data. Would be equal to If1. Would be equal to If1/2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements: To control the speed of a dc shunt motor above the base speed over a reasonably wide range, the motor must 1. have compensating winding 2. have interpole winding 3. be started using a 3-point starter 4. be started using a 4-point starter Of these statements 1, 2 and 4 are correct 2 and 4 are correct 1 and 3 are correct 1, 2 and 3 are correct 1, 2 and 4 are correct 2 and 4 are correct 1 and 3 are correct 1, 2 and 3 are correct ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a lap winding dc machine number of conductors are 100 and number of parallel paths are 10. Find the average pitch 50 100 10 1 50 100 10 1 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A Shunt generator running at 1000 rpm has generated emf of 100 V. If the speed increases to 1200 rpm, the generated emf will be nearly 140 V 240 V 175 V 120 V 140 V 240 V 175 V 120 V ANSWER DOWNLOAD EXAMIANS APP
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