NTPC Previous papers

1)      Steady state acceleration error of type 1 system,

a.      0

b.      1

c.       Infinity

d.

2)    Position and velocity of type 2 system,

a.    Constant, Infinity.

b.    Zero, Constant.

c.    Zero, Zero.

d.    Constant, Constant.

3)      In a diode ‘cut-in’ & ‘forward voltage drop’

a.      0.7, 0.7

b.      0.7, 1

c.      0.7, 0.6

d.      1, 0.7

4)      Potential value of α in a transistor? β

a.      1.

b.      1.

c.       Negative.

d.       Between 0.95 & 0.99

5)       What is the relation between α & β of a transistor?

6)       In SCR dv/dt protection achieved by

a.       RL in Series.

b.       RC across.

c.       L in series.

d.       RC in Series.

7)      Placing inverter between both input of S-R Flip-Flop results in,

a.      J-K Flip Flop.

b.      D Flip-Flop.

c.      T Flip-Flop.

d.       Master Slave J-K Flip-Flop.

8)      Which have Max. Distortion?

a.      Class A Amplifier.

b.      Class B Amplifier.

c.      Class AB Amplifier.

d.      Class C Amplifier.

9)   Which is Initial Value Theorem,

         4 options were there.

10)  By increasing Frequency, power dissipation in CMOS,

a.       reduce.

b.       Increase.

c.       Unchanged.

11)  Anderson Bridge used to measure

a.     Inductance

b.     Capacitance.

c.   

d.

12) Laplacetransform of e-atsin wt.

13)Lap winding is mostly suitable for

a.      Low Voltage, High Current Machines.

b.      High Voltage, High Current Machines.

c.       High Voltage, Low Current Machines.

d.      Low Voltage, Low Current Machines.

14)  Turn-on time of SCR in Series with RL circuit can be reduced by,

a.       Increasing ckt resis. R.

b.      Decreasing ckt resis R.

c.      Increasing ckt ind. L.

d.      Decreasing ckt. Ind. L.

15)  In Two-Wattmeter Method of measuring power, the reading of  2 W.M. will be

a.      VLILcos(30+φ), VLILcos(30+φ)

b.      VLILcos(30–φ), VLILsin(30–φ)

c.       VLILcos(30–φ), VLILcos(30+φ)

d.     VLILcos(30–φ), VLILsin(30+φ)

16)  In Railways the CB used is

a.       SF6.

b.      ABCB.

c.       VCB.

d.      OCB.

17)  What is the short-circuit admittance parameter Y11 of the following п-Network?

    ____________Yc____________

           |                                   |                                 

           |                                   |

          Ya                               Yb

           |                                   |

           |                                   |        

18)  What is 7483?

      4 options were given.

19)  8080 is

a.       16 bit.

b.      24 bit.

c.       64 bit.

d.      32 bit.

20)  A question on 4 types of CRO with their application. You have to match them.

21)  Kirchoff’s Law is applicable for.

a.       AC ckt. only.

b.      DC ckt. only.

c.       Both AC & DC ckt.

d.      Passive ckt. Only.

22)  What is Synchronous Reactance?

23)   A Q was from DC M/c.; 4 type Generators(series, shunt, cumulative, ______ ) and their appl.(arc welding, booster, ______, ______ ) Given, you have to match them.

24) Q came from II-quadrant operation of DC drive.

25) An inverted sawtooth wave form was given which had (-)ve Y-axis magnitudeon 30 and time value on X-axis were 5 & 7.

      You have to choose the correct mathematical form of that wave from 4 options.

26) A simple ckt with a 20V source, a diode and a 10 Ohm resistance in series was given,

       The condition was 'if the diode is ideal' then what will be the current value?

27) Which is universal GATE?

            a. NAND & NOR.

            b. NAND.

            c. NOR.