SSC JE electrical question paper 2008

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1. Motor used for elevators is generally ?




... Answer is C )
AC slip ring induction motor or DC compound motors are prefer for lifts. Shunt type commutator motors are preferred in case of single phase installation.

2. Which of the following is not a welding accessory ?




... Answer is D)
A number of items must be used with a welding machine to complete the setup. The major items are the welding cables, the electrode holders, and the work clamps.

3. The transformer used for AC welding sets is ?




... Answer is C)
In the electric welding transformer the secondary side has low voltage and high current (typically 200 to 600 amps) because for electric welding high current is required. Hence, the transformer required for welding is step down type.

4. A relay performs the function ?




... Answer is B)
In electrical engineering, a protective relay is a relay device designed to trip a circuit breaker when a fault is detected.

5. HRC fuse provides best protection against ?




... Answer is D )
They provide high-speed operation in short circuit and over current protection.

6. The scale of moving iron (M.I) instrument is ?




... Answer is B)
In moving iron instrument, usually the scale is compressed or cramped at its lower and higher end.


7. The power factor of industrial loads is generally: ?




... Answer is B)
Power factor if industrial unit depends on the mix of all types of machines, ovens, pumps, lighting etc.The power factor of industrial loads is generally lagging ...

8. The value of demand factor is: ?




... Answer is A)
As demand factor is

maximum demand of system /Total connected load on system


As you can see total connected load is always greater than maximum demand of system in specified time period . So demand factor is always less than 1.



Load factor is

Average load / maximum load during a given period

It is always less than 1 .Because maximum load is always greater than average load.



9. The slip of an induction motor under full load condition is about: ?




... Answer is B)
Watch the Video.

10. The motor used in ceiling fans is: ?




... Answer is C)
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11. A dynamometer type wattmeter responds to the ?




... Answer is A)
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12. Which of the following meters is an integrating type instrument ?




... Answer is D)
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13. For battery charging which of the following DC generators is used ?




... Answer is B)
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14. The no load speed of DC series motor is ?




... Answer is C)
Watch the Video.

15. A circuit component that opposes the change in circuit voltage is: ?




... Answer is B)
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16. A series resonant circuit implies: ?




... Answer is B)
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17. A current i = (10 + 10 sunt amperes is passed through moving iron type ammeter. Its reading will be ?




... Answer is C)
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18. A DC ammeter has resistance of 0.1 Ω and current range is 0 - 100A. If the range is to be extended to 0- 500A, then meter requires shunt resistance of ?




... Answer is C)
Watch the Video.

19. In which type of welding is a pool of molten metal used ?




... Answer is A)
Watch the Video.

20. Plane and butt welds may be ?




... Answer is A)
Watch the Video.

21. In arc welding, arc is created between the electrode and work by: ?




... Answer is D)
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22. Mho relay is used to protect ?




... Answer is C)
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23. For arc heating, the electrodes are made of ?




... Answer is C)
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24. The most common type of three phase in unsymmetrical fault is ?




... Answer is A)
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25. If supply frequency increases, the skin effect is: ?




... Answer is B)
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26. A PN junction is: ?




... Answer is A)
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27. Megger is an instrument to measure: ?




... Answer is B)
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28. Arc lamp operates at ?




... Answer is A)
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29. The value of V in the circuit shown in the given figure is: ?





... Answer is C)
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30. Two heaters rated a 1000W, 250V each are connected in series across a 250V, 50 Hz AC mains. The toral power drawn from the wupply would be: ?




... Answer is B)
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31. Area of hysteresis loop represents: ?




... Answer is D)
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32. Two coupled coils with L1 = L2 = 0.6 have a coupling coefficient of K = 0.8. The turn ratio N1/N2 is ?




... Answer is C)
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33. The eficiency for maximum power transfer to the load is: ?




... Answer is B)
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34. In synchronous motor, minimum armature current occurs at: ?




... Answer is D)
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35. High speed alternators usually have: ?




... Answer is B)
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36. The field winding of an alternator requires: ?




... Answer is A)
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37. The Rotor input when, rotor copper loss in an induction motor is 600 W and slip is 3% is: ?




... Answer is C)
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38. Inter poles are meant for ?




... Answer is D)
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39. The purpose of the conservator in a transformer is: ?




... Answer is D)
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40. In case of a power transformer, the no load current in terms of rated current is: ?




... Answer is B)
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41. Copper loss of transformer at 7 8 th full load is 4900 W, then its full load copper loss would be: ?




... Answer is B)
Watch the Video.

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