Electrical Machines Find the reactance voltage when current is changed from -2A to 2A in 4 sec and self inductance is 1H? 1 V 2 V 4 V 0 V 1 V 2 V 4 V 0 V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The direction of generated emf in the armature coil of a DC machine is 1. the same as that of the current in a generator 2. the same as that of the current in a motor 3. opposite to that of the current in a generator 4. opposite to that of the current in a motor From these, the correct answer is 2, 4 2, 3 1, 3 1, 4 2, 4 2, 3 1, 3 1, 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Transformer cooling and insulating oil must be of low viscosity. high viscosity. low BDV. low resistivity. low viscosity. high viscosity. low BDV. low resistivity. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The speed of a cumulatively compound DC motor can be controlled by varying Shunt field resistance control. Armature voltage control. Any of above. Armature resistance control. Shunt field resistance control. Armature voltage control. Any of above. Armature resistance control. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The volt-ampere euation for a long-shunt compound motor is given by Vt = Ea + Ia(ra + rs) Vt = Ea + Iara+ ILrs Vt= Ea– Iara Vt= Ea + Iara Vt = Ea + Ia(ra + rs) Vt = Ea + Iara+ ILrs Vt= Ea– Iara Vt= Ea + Iara ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a single phase capacitor start induction motor which of the following is valid? Rotation can be changed by interchanging supply terminals. Rotation can be changed by reversing main winding terminals. None of these. Direction of rotation cannot be changed. Rotation can be changed by interchanging supply terminals. Rotation can be changed by reversing main winding terminals. None of these. Direction of rotation cannot be changed. ANSWER DOWNLOAD EXAMIANS APP
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