OCES or DGFS Exam Papers

I am looking for previous year question papers of BARC OCES or DGFS Exam so please provide me the same for preparation?

[Arun Vats]

Here I am providing you previous year question papers of BARC OCES or DGFS Exam for your preparation.

Bhabha Atomic Research Centre (BARC) OCES or DGFS Exam Paper 1:

1. Distinction between FM and PM at high frequencies.

2. Which of these has the least propagation delay RTL/ECL/I2L/CMOS.

3. Switching speed of CMOS is affected/unaffected by changes in supply voltage.

4. Which of these provides a measure of heart rate P/QRS complex/T/none of these.

5. Given a ckt of a logarithmic amplifier you had to identify what ckt was it.

6. JFET can operate in depletion/enhancement/both/none of the above modes.

7. When a BJT operates in saturation the junctions are fwd biased/reverse biased/...

8. BIBO stability criterion implies that poles are within/outside/on the unit circle.

9. For faithful amplification of low amplitude signals the cut-off/active/saturation regions of a

transistor is used.

10. Lissajous pattern of a signal rotates 36 times per minute. if the oscillator frequency is 560 kHz

then the unknown freq is...

11. % resolution of a 10 bit ADC.

12. To obtain 10 mV resolution on 5 V range how many bit DAC is to be used..

13. Why is LCD preferred to LED.

14. How will 0.6973 be displayed on 10 V range of a 4 1⁄2 digit multimeter.

15. Which of the following cannot be used for an automatic feedback temp ctrl system

thermocouple/thermometer/thermistor/IC sensor.

16. Y(n)=X(-n+3) is an example of a linear/non linear and shift variant/invariant system.

17. The falling body method is used to determine viscosity/humidity/....

18. Which of these methods of viscosity measurement gives greatest accuracy falling body

method/rotating cylinder method/both/...

19. Some question on gas chromatography

20. A device having a rotor with 3 Y-connected coils and a stator is likely to be a

synchro/RVDT/control transformer/...

21. In a twisted ring counter the initial count is 1000. after the 4th clock pulse its state will be....

22. A 240 kHz signal is given into a 3 bit binary ripple counter. The lowest o/p freq obtainable is....

23. For parity bit checking which of the following gates can be used XOR/NAND/OR/XNOR.

24. Why is a BJT called so..

25. Identify the expression for gauge factor of a strain gauge among the given options.

26. In a semiconductor strain gauge as tensile strain is applied what changes take place in the n and

p areas..

27. How does a radioactive level gauging system work...

28. A capacitive transducer measuring level works on the principle of change in distance between

plates/change in dielectric strength/...

29. For maximum power transfer in an AC circuit the condition to be satisfied is

ZL+ZS=0/XL+XS=0/none of these/....where l and s refers to load and source respectively.

30. Find the transfer function from a block diagram.


Bhabha Atomic Research Centre (BARC) OCES or DGFS Exam Paper 2:

1. matched pair of transistors is particularly useful for

A) Differential amplifier

B) High gain amplifier

C) High input impedance amplifier

D) Low output impedance amplifier

2. Magnetic flux density can be measured by using

A) ,Q, meter

B) AC voltmeter

C) Hall probe

D) Energy meter

3. In closed loop type of A/D conversion the fastest technique is :

A) Successive Approximation

B) Flash

C) Dual slope integration

D) Counter-ramp

4. When bearing life L10 represents (bearings 10%survive,bearings 10% fails, none )

5. For welding high carbon steels which type of flame is used (oxidizing, carburizing, neutral,

none)

6. Arrange the following cutting tools in decreasing order of machining hardness...Ceramics

7. When P1 and P2 are the loads acting on bearings with life L1 and L2 then L1/L2=?

L1/L2={P2/P1}10/3

8. Product simplification does not mean? (Product characterization)

9. Which of the following process has the most scope in manufacturing? CAD/CAM, CAM,

CIM, All the above.

10. Rankine cycle efficiency for same parameters increases mostly with_(reheat,

regeneration, super heating )

11. Ericson cycle with all reversible processes assume_(carnot cycle,stirling,brayton

12. Air delivery tank at outlet of reciprocating compressor is provided for_ (provide constant

pressure, avoid cavitation, )

13. High speed centrifugal pump has _? (vanes faces in forward direction

side,backward,radial vanes)

14. Thermal efficiency in decreasing order_? (Otto cycle>dual cycle>diesel cycle)

15. Connect two 1O resistors in series, then connect two 1H inductors across one of the

resistors such that the ckt looks like a 1O resistor in series with a ?-section of a resistor and

two inductors. With the series resistance on the i/p side, calc the transfer function of this ckt

16. Inverse laplace transform of 1/s2[d/ds(e-3s/s)]

17. Lower useful input limit of a transducer is determined by...

18. Air-cored inductors are used for low frequency/high frequency/equal frequency

operations.

19. Given 4 pole-zero plots identify which one corresponds to the driving point impedance of

a series resonant ckt.

20. Expression for d(n): u(n)-u(n-1)/ u(n-1)-u(n+1)/ u(n)+u(n+1)/...

21.Relation between laplace and z-transform: s=z/ s=ln z/ s=( ln z/T) /...

22. Maxm and minm probability error among ASK,PSK,FSK,DPSK etc

23. Which of the following is a non linear modulation scheme: PAM/QAM/PCM/...

24. Match the following functions: e-t , e-t + et, sin(pt) with causal and stable system, causal

and unstable system, etc.

25. Given a ckt with a 50 O resistor in series between two voltage sources of 10 V and 5 V

magnitude calc power delivered by 5 V source.

26. Laplace transform of e-3tu(t)+e2tu(-t).

27. Which photodetector has output affected by own intrinsic noise: PN/APD/PIN/all.

28. AC signal conditioning is used for inductive and capacitive/resistive/piezoelectric

transducers/all of the above.

29. When I mode is added to proportional control system stability increases/ decreases/

steady state performance deteriorates/damping increases.

30. Reset control is another name for integral/derivative/proportional/.... Control.