Electrical Machines In travelling cranes for hoisting and lowering which type of motor is preferred? Single phase induction motor. Synchronous motor. AC slip ring motor. DC series motor. Single phase induction motor. Synchronous motor. AC slip ring motor. DC series motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Armature reaction depends on which of the following? magnitude of load current power factor of load both 1 and 2 None of these magnitude of load current power factor of load both 1 and 2 None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A commutator in DC machines can 1. provide half-wave rectification 2. Provide full-wave rectification 3. convert ac to dc 4. Convert dc to ac 5. provide controlled full-wave rectification From these, the correct answer is 2, 3, 4, 5 2, 3 ,5 2, 3, 4 1, 2, 3 2, 3, 4, 5 2, 3 ,5 2, 3, 4 1, 2, 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A synchorous generator connected to an infinite bus is over excited. Considering only the reactive power from the point view of the system the machine acts as None of these. A resistor. an inductor. A capacitor. None of these. A resistor. an inductor. A capacitor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Stability of a synchronous motor ---------- with the increase in excitation. increases remains unaffected any of the above decreases increases remains unaffected any of the above decreases ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the frequency of input voltage of a transformer is increased keeping the magnitude of voltage unchanged, then Ph will decrease but Pe will remain same Ph will increase but Pe will decrease Pe will increase but Ph will decrease both hysteresis loss(Ph) and eddy current loss(Pe) will increase Ph will decrease but Pe will remain same Ph will increase but Pe will decrease Pe will increase but Ph will decrease both hysteresis loss(Ph) and eddy current loss(Pe) will increase ANSWER DOWNLOAD EXAMIANS APP
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