Electrical Machines Which of the following transformer insulating oil generally used in India? Paraffin based insulating oil. Naphtha based insulating oil. Aromatics based insulating oil. Olefin based insulating oil. Paraffin based insulating oil. Naphtha based insulating oil. Aromatics based insulating oil. Olefin based insulating oil. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The working principle of transformer depends on Newtons law. Coulombs law. Amperes law. Faradays law of electromagnetic induction. Newtons law. Coulombs law. Amperes law. Faradays law of electromagnetic induction. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If a DC Series motor is connected across an AC supply it will run at normal speed. burn. run at lower speed. not run. run at normal speed. burn. run at lower speed. not run. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following motor has negative speed regulation? Series motor Cumulative compound motors Shunt motor Differential compound motor Series motor Cumulative compound motors Shunt motor Differential compound motor ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following factors improve commutation in a dc machine ? 1. High contact resistance of brushes 2. High inductance of the coils undergoing commutation 3. Shifting of brushes in the direction of rotation for a generator and in the opposite direction For a motor 4. Narrow width for the commutation bars Select the correct answer using the codes given below : Codes : 1, 2, and 3 1, 2 and 4 2, 3 and 4 1 and 3 1, 2, and 3 1, 2 and 4 2, 3 and 4 1 and 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4-pole dc generator runs at 1500 rpm. The frequencyof current in the armature winding is 100 Hz 50 Hz 25 Hz 0 Hz 100 Hz 50 Hz 25 Hz 0 Hz ANSWER DOWNLOAD EXAMIANS APP