| 1. | The function of starter in electric motor is ? | |
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starting purpose
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avoid the over load
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minimize high starting current
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All option are correct
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Report Question| 2. | What will be the capacity of four capacitors of equal capacity C, when connected in series ? | |
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4C
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C/4
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C
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3/4C
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| 3. | Principles are use in street lighting is ? | |
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diffusion and specular reflection
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induction
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electromagnetic
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electrostatic
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| 4. | Which type of starter used for fluorescent lamp ? | |
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glow type
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star/delta starter
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autotransformer
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3 point
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| 5. | The illumination level in houses is in the range ? | |
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10-20 lumen/m²
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30-50 lumen/m²
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40-75 lumen/m²
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100-140 lumen/m²
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| 6. | Which of the following has the highest value of thermal conductivity ? | |
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Water
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Steam
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Solid ice
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Melting ice
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| 7. | A domestic mixer uses the following motor ? | |
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induction motor
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reluctance motor
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universal motor
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permanent magnet synchronous motor
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| 8. | Low frequency supply is necessary for direct core type induction furnaces because ? | |
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Magnetic coupling between the primary and secondary circuit is poor.
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With normal frequency supply the electro-magnetic forces cause severe stirring action in the molten metal.
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Both Magnetic coupling between the primary and secondary circuit is poor and With normal frequency supply the electro-magnetic forces cause severe stirring action in the molten metal.
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None of Magnetic coupling between the primary and secondary circuit is poor and With normal frequency supply the electro-magnetic forces cause severe stirring action in the molten metal.
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| 9. | A locomotive exerts a tractive effort of 35,300 N in hauling a train at 48kmph on the level track. If the motor is to haul the same train on a gradient of 1 in 50 and the tractive effort required is 55,180N, determine the power delivered by the locomotive if it is driven by (i) dc series motors (ii) induction motors. ? | |
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635.7kW
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735.7kW
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725.6kW
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76.6kW
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| 10. | Which of the following has the highest mobility ? | |
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Neutron
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Electron
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Positive ions
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Negative ions
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