| 1. | Power factor is highest in case of ? | |
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Mercury arc lamp
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Sodium vapour lamps
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Tube lights
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GLS lamps
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Report Question| 2. | The process of heat transfer during the re-entry of satellites and missiles at very high speeds, into earth's atmosphere is known as ? | |
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Ablation
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Radiation
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Viscous dissipation
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Irradiation
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| 3. | A pole-changing squirrel cage induction motor employed in derricks has four, eight and twenty four pole. The lowest speed is used in ? | |
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hoisting
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landing the load
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lifting
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lowering
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| 4. | In heating the ferro-magnetic materials by induction heating, heat is produced owing to ? | |
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Flow of induced current through the charge.
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Hysteresis loss occurring below Curie temperature.
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Hysteresis loss as well as eddy current loss occurring in the charge.
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Any of the factors given in the options.
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| 5. | A 30kW rated output, 400V, 3 phase delta connected, 4-pole, 50 Hz induction motor full load slip of 5%. If the ratio of standstill reactance to resistance per rotor phase is 4 estimate the full load speed. ? | |
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1425 rmp
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1500 rmp
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1350 rmp
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1625 rmp
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| 6. | The conduction band is ? | |
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the region of free electrons
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concentrated holes for the flow of current
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always above the forbidden energy level
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a range of energies corresponding to the energies of the free electrons
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| 7. | The motor that is used for intermittent, high torque loads is ? | |
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DC shunt motor
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DC series motor
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differential compound motor
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cumulative compound motor
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| 8. | IDC in a full wave rectifier is ? | |
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2Im/n
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Im/n
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Im/2n
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4Im/n
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| 9. | The relationship between alpha and Beta factors of a transistor can be defined as ? | |
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Beta = 0 / (1-alpha)
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alpha = Beta / (Beta-1)
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alpha.Beta = 1
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Beta = alpha / ( alpha - 1)
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| 10. | The operating point is also called the ? | |
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cut-off point
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quisecent point
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saturation point
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None of these
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