BHEL Job Interview Paper for Engineer Trainees- 2008 (Bangalore)


They have called people in morning and afternoon shifts, nearly 15-16 people per shift. We were asked to bring interview call-letter, biodata form, TA form, all original mark-sheets and one Xerox copy of all. When we reached the venue, first they verified all documents. SC/ST people have to show original caste certificate. They have a list of central reserved castes and your caste serial no. will be verified with that. The traveling allowance will paid there itself to all. After that we were made to sit and wait for our turns.


About Biodata form –

They will post it in web site, it has all relevant information about you similar to a resume, (so we do not need any resume there) like your name, address, all semester marks details, 10-12th marks, college, area of interest, main subjects in semesters, your current job profile, have you appeared for any other govt./PSU exams etc.


While preparing for interview, everybody told me to stress on technical and final year project and for HR questions, but that proved wrong. My timing was in the afternoon shift at 2 pm, and I was called nearly at 3.30 pm. There were 3 people in the panel. They seem to be very experienced ones.


They started with the question –

Q. Why I want to join BHEL.

Though I was not prepared for this question, as I was expecting technical questions, but I tried answering that I always wanted to join BHEL, I am very adjustable, and I can perform well in the areas in which they will train me. But the people were not much satisfied; they also asked me to give a solid example for my adjustability.


Q. They asked about my family, father’s job, brother-sisters etc..

The people seem to be very lenient while asking, infact some-times I felt that they are not taking any interview. We were simply chatting, laughing in the interview room.


Q. Next they asked what preparations I have done for the interview.

I told I have checked the BHEL’s site and collected some information about it. Next I have prepared my area of interest i.e. Digital electronics. My 2nd area of interest was Microprocessors 8085 and they started with that.


Q. What do mean by 8085.

I told it’s the serial no. of the device given by the company Intel. But they were not satisfied and told it must have some meaning. I told may its 8 because it’s a 8-bit processor and about other digits no idea.


Q. How many types of microprocessors do we have?

I told 8 bit, 16 bit, 32 bit.


Q. Do we have any 64 bit processor?

I never heard of it so told so.


Q. What is RISC/CISC?

I answered RISC is reduced instruction set computing and CISC is complex instruction set computing.


Q. What’s the difference between them?

I told RISC is generally used for high speed switching operations and CISC is for general purpose like 8085.


Q. Do we use microprocessors nowadays?

I told we generally go for microcontrollers these days.


Q. What are microcontrollers?

I said it has memory inbuilt in it apart from microprocessor architecture.


Q. What do you think the CPU we use has microprocessor in it.

I told it has but not only microprocessor. It has other components also.


Q. What do you think the other components are?

The answer of this question doesn’t click me there so I told no idea.


Q. What do think Pentium uses RISC or CISC?

I was not sure with this so answered we can use RISC


Q. They told don’t tell we can, what we exactly use

I told truly that specifically I don’t know.


They stopped with this. I felt that they were not very specified with some questions but the best part was I never go nervous and maintained a smile through-out. They have not at all mentioned about final year project or any other curriculum subject. My advice to electronics people is – try having a different area of interest other than microprocessors because in my batch some 7-8 electronics people came for interview all having same microprocessor as area of interest. The people got little bugged up with and asked some people don’t you have some different subjects.



BHEL Mechanical Engineering Paper



I attended the BHEL Engineer Trainee written test in Mechanical stream. They conducted for four brances in Engineering: Comp sci, ECE, EEE and Mechanical. In Mechanical Branch there were a total of 240 questions. 120- Technical questions in Mechanical Engineering. 120- General Apptitude questions. (Quantitative Aptitude, Reasoning Ability, Logical thinking, English usage).


The questions were mainly asked in




•Engineering Mechanics


•Theory of machines


•Production tech


If you are thorough with your subject, you can really do well in this session.


[One Mark for correct answer, 1/5th for wrong answer. Five choices were given] Some questions which i remember are :


1)Unit of Entropy (J/kg K or kJ/kg K)?


2)A mass of 100kg is falling from a height of 1 m and penetrates the sand into for 1 m. What is the resistance force given by sand?


3)Ratio of specific heats of air ? (1.41)


4)A body weighs 3 kg in air. If it is submerged in a liquid, it weighs 2.5 kg. What is the specific gravity of the liquid ?


5)Two cars travell in same direction at 40 km/hr at a regular distance. A car comes in a opposite direction in 60km/hr. It meets each car in a gap of 8 seconds. What is the distance between them?


6)A simple problem involing in hoops stress. For sphere: M= [3/2]*p*V* [density of pressure vessel material/Maximum working stress it can tolerate] For Thin walled pressure walls: Hoops stress or stress in the radial direction =p*r/2t?


7) A problem in force calculation in a body moving in a inclined surface?


8)Composition of bronze?

ans. Copper+zinc.


9) Compostion of stainless steel.?

ans. iron+chromium+nickel+carbon.


10) CI is manifactured in which process?

ans. cupola process


11)What percentage of carbon is preset in pig iron?

ans. 4.5 to 6%.


12)Water is available at 10m height. What is the pressure available?

ans= pressure=density*g*height;




13)What will happen if the speed of the centrifugal pump doubles?


14)The unit eV is widely used in ?

ans. Nuclear and atomic physics.


15)What will happen to the resistance, when the diameter of the conductor is doubled?


16)The power comsumed by a electrical device is 1000W at 250V, What is the resistance in the device?

ans. Power= Voltage*current,



amps. V=IR,

Therefore R=250/4=62.5 ohms.


17)Why DC current is not used in transformer?


18)On what principle the sonar/ radar works?


19)Bending moment diagram for the UDL is in what shape?


20)Function of the distributor in petrol vehicles?

ans. Spark timing.


21)Which is not present in CI engines?

ans. carburrettor.


22)What will happen if one cylinder recieves more amount of fuel spray from injectors than other injectors?


23)Purpose of draft tube in hydraulic turbines?


ans. The purpose of a draft tube is toconvert some of the kinetic energy of the flow from the runner (the rotating part of the turbine) intopressure energy and thereby increase the efficiency ofthe hydro power turbine.


24)What is the effect or reheater in the gas turbine?


The advantage of reheater is significantly increased thrust; the

disadvantage is it has very high fuel consumption and inefficiency.


25)Problems involving with fricition coefficient.


26)Factor of safety = Yeild stress/Working stress.


27)Which is the example of non parallel power transmission (Universal coupling)?


28)For perpendicular shafts worm gear is used?


29)A planet gear with 25 teeth is meshed with a sun gear of 100 teeth. Both are connected using a arm. How many rotations are needed for planet gear to complete one rotation around the sun gear?


30)What is equivalent spring constant for spring in parallel?


31) Some questions was asked related to boundary layer and vortex flow.


32) 5 questions were asked in PERT, Process planning, Product planning, Break even analysis.


33)How are tungsten and sintered composite materials are machined?

(Electro Discharge Machining, EDM)


General Apptitude:


very easy.


There are 120 questions .




Detect the words with wrong spellings (5 questions).

Fill in the blanks with appropriate words(5 questions).

Two reading comprehensions were given(10 questions).

Find the error in the sentence (8 questions).




Seating arrangement problems.

Find the relation between them.


Quantitative ability:


50% of the questions are from basic geometry .

Remaining were very general and easy. But many questions are there that's y you should consider time factor and be quick.


BHEL Placement Papers (2008)


1. The ratio of two specific heats of air is equal to. = 1.41


2. A perfect gas at 270C is heated at constant pressure till its volume is double. The final temperature is = 3270C


3. An engine operates between temperature of 9000K and T2 and another engine between T2 and 8000K. For both to do equal work, value of T2 will be. = 6500K


4. Internal energy of a substance depends on = Temperature


5. Work done in compressing 1kg of gas adiabatically from p1,V1,T1 to p2, V2, T2 is equal to = Cv(T2-T1)


6. The unit of entropy is = J/kg 0K


7. Indicated power of a 4-stroke engine is equal to = pLAN/2


8. Which of the following is not an internal combustion engine : a) 2 stroke petrol engine b)4 stroke petrol engine c) Diesel engine d) steam engine e) Gas turbine. = (d)


9. If one cylinder of a diesel engine receives more fuel than the others, then for that cylinder the: a) exhaust will be smoky b) piston rings would stick into piston grooves c) exhaust temperature will be high d) engine starts overheating e) all of the above. = (e)


10. The spark plug gap is normally maintained at: = 0.45 to 0.6mm


11. A distributor in spark ignition engines performs the function of : = Providing the correct firing order in engine


12. Which of the following does not relate to C.I. engine:: a) fuel pump b) fuel injector c) governor d) carburetor e) flywheel = (d)


13. Air fuel ratio in a jet engine is = 60:1


14. What is the value of Prandtl No.?


15. In domestic refrigerator, the tubes at the back of the refrigerator are: a) evaporator b) condenser c) capillary tubes d)………


16. Which refrigerants has the highest critical point temperature. = Freon-11


17. Wet bulb temperature is. = indication of amount of moisture in air


18. On psychrometric chart, dry bulb temperature lines are. = Vertical


19. Surface tension has the units. = newtons/m


20. The line of action of the buoyant force acts through the. = centroid of the displaced volume of fluid


21. A pressure of 25m of head of water is equal to. =245kN/m2


22. For a submerged body to be in stable equilibrium, the centre of gravity should be. =Below the centre of buoyancy.


23. The actual velocity at vena contracta for flow through an orifice from a reservoir of height H=?. =Cvv2gH


24. A body weighing 2kg in air weights 2.5kg when submerged in water. Its specific gravity is. = 6


25. In a free vortex motion: = each particle moves in a circular path with a speed varying inversely as the distance from the centre.


26. A centrifugal pump has speed-1000rpm, Flow-1200l.p.m, Head-20m, Power-5H.P. If its speed is increased to 1500rpm, new flow will be.: = 1800l.p.m


27. Runaway speed of a hydraulic turbine is: = the speed if the turbine runner is allowed to revolve freely without load and with the wicket gates wide open.


28. 10m of water column is equal to = 100kN/m2


29. M.I. of a circular area about an axis perpendicular to the area is: = pr4/2


30. A projectile is fired at an angle ? to the vertical. Its horizontal range will be maximum when ? is . =450


31. An elevator weighing 1000kg attains an upward velocity of 4m/sec in two seconds with uniform acceleration. The tension in the supporting cables will be = 1200kg.


32. A 13m ladder is placed against a smooth vertical wall with its lower end 5m from the wall. What should be the co-efficient of friction between ladder and floor so that it remains in equilibrium. = 0.21


33. A car is moving with a velocity of 60km/hr and possesses energy of 5×105 joules. The mass of the car will be. =3000kg.


34. If l is the span of a light suspension bridge whose each cable carries total weight (w) and the central diop is y, the horizontal pull at each support is: = wl/y OR


35. A beam of length l, having uniform load w kg/unit length is supported freely at the ends. The moments at mid span will be: = wl2/8.


36. A boiler shell 200cm dia and plate thickness 1.5cm is subjected to internal pressure of 1.5MN/m2, then the hoop stress will be. = 100N/m2


37. 100KW is to be transmitted by each of two separate shafts. A is turning at 250rpm and B at 300rpm. Which shaft must have greater diameter.: = B


38. Two identical leaf springs of spring constant k are arranged like cantilevers in parallel and attached at free end by a spring of spring constant k. The equivalent spring constant of combination is; = 1.5k.


39. Automobile steering gear is an example of: = lower pair.


40. The type of coupling used to join two shafts whose axes are neither in same straight line nor parallel, but intersect is. = Universal coupling.


41. To transmit power from one rotation shaft to another whose axes are neither parallel nor intersecting, use: = Spiral gear.


42. A gear having 100 teeth is fixed and another gear having 25 teeth revolves around it, the centre lines of both gears being joined by an arm. How many revolutions will be made by gear of 25 teeth for one revolution of arm. = 5 rev.


43. The secondary critical speed of a shaft occurs at: = twice the speed of primary critical speed.


44. Brittle coating technique is used for: = experimental stress analysis.


45. Factor of safety is the ratio of: = yield stress/working stress.


46. Type of gear used for non-intersection perpendicular shafts: = Hypoid gears.


47. Corrosion resistance of steel is increased by adding: = Chromium & Nickel


48. The product of Cupola is called: = cast iron


49. Brinell tester uses a hardness steel ball of size: = 10mm


50. Sintered and tungsten carbides can be machined by: = EDM


51. What kind of abrasive cut off wheel should be used to cut concrete, stone and masonry? =Diamond grit.


52. In break-even analysis, total cost consists of: = Fixed cost + Variable cost.


53. The amount deducted from the salary of workers towards employees provident fund is : =deposited in the account of worker with Provident Fund Commissioner.


54. PERT is: = event oriented technique


55. Bar charts are suitable for: = minor works.


56. ? on a PERT/CPM chart represents: = a significant event representing some mile-stone


57. Electron volt is the unit of : = Energy.


58. Seamless tubes are made by?


59. Reheating in gas turbine results in: = increase of work ratio and decrease of thermal efficiency.


60. Why DC current is not used in transformer?


61. What is the purpose of draft tube in hydraulic turbines: = to convert the kinetic energy into pressure energy.


62. A mass of 100kg is falling from a height of 1m and penetrates the sand to 1m. what is the resistance force of the sand?


63. Two cars travel in the same direction at 40km/hr at a regular distance. A car comes in the opposite direction at 60km/hr. It meets each car in a gap of 8 seconds. What is the distance between the two cars?


BHEL Sample Placement Paper Pattern


Consider the following expressions indicating the step or impulse response of an initially relaxed control system-

1. (5 – 4e-2+) u(t)

2. (e-2t +5) (u(t))

3 .V(t) + 8e-2t u(t)

4 . V(t) + 4e-2t 4(t)


Those which correspond to the step and impulse response of the same system include- 1&3

Which is the following relate to rational transfer function of a system-

1. Ratio of Fourier transform of output to input with zero initial conditions.

2. Ratio of Laplace transform of output to input with zero initial conditions.

3. Laplace transform of system impulse response.

4. Laplace transform of system unit step response select the correct answer using the codes given below.



a.) 1 and 4

b.) 2 and 3

c.) 1 and 3

d.) 2 and 4


For the signal g (t) – 10 cos (50 pt) cos2 (150at)

The Nyquist sampling state in t seconds is

a.) 150 samples per second

b.) 200 samples per second

c.) 300 samples per second

d.) 350 samples per second



In the case of a 70 MHz 1F carries for a transponder band width of 36 MHz; energy must lie between – MHz.

a.) 34 and 106

b.) 52. And 88

c.) 106 and 142

d.) 34 and 142



Radar used to eliminate clutter in navigational application is –

a.) Pulse radar

b.) Tracking radar

c.) MTI radar

d.) Mono pulse radar



The 1.55 mm windows is not yet in use with fiber optic systems because –

a.) The attenuation is higher than at 0.85 mm

b) The attenuation is higher than at 1.3mm

c.) Suitable laser devices have not yet been developed

d.) It does not lend itself to wavelength multiplexing



Pre-emphasis in FM systems involves-

a.) Compression of the modulating signal

b.) Expansion of the modulating signal

c.) Amplification of lower frequency components of the modulating signal.

d.) Amplification of higher frequency components of the modulating signal.



In a terrestrial microwave system transmission of signals is achieved through-

a.) reflection from the ionosphere

b.) line of sight mode

c) reflection from the ground

d.) diffraction from the stratosphere.


Casse grain feed is used with a parabolic reflector to

a.) increase the gain of the system

b). increase the bandwidth of the system

c.) reduce the size of the main reflector

d.) allow the feed to be placed at a convenient point.


In most microwave communication link rain drop attenuation is caused due to-

a.) scattering of microwaves by water drops of specific size.

b) scattering of microwaves by a collection of droplets acing as a single body.

c.) absorption of microwaves by water and consequent heating of the liquid

d.) absorption of the microwaves by water vapor in the atmosphere.



When a (75 – j40)W load is connected to a coaxial line of Z0 = 75 W at 6MHz then the load matching on the line can be accomplished by connecting-

a.) A short – circuited stub at the load

b.)An inductance at the load

c. )A short circuited stub at a specific distance from the load

d.)none of the above


As compared to analog multimeters, digital multimeters are –

a.) less accurate

b.) more accurate

c.) equally accurate

d.) none.


When a signal of 10 mV at 75 MHz is to be measured then which of the following instruments can be used –

a.) VTVM

b.) Cathode ray oscilloscope

c.) Moving iron voltmeter

d.) Digital multimeter


Amplifier of class B has high theoretical efficiency of 78.5 percent because-

a.) It is biased almost to saturation

b.)Its quiescent current is low

c.)It’s output is an exact replica of it’s input

d.)It is biased well below cut off


The coupling that produces minimum interference with frequency response is-

a.) Direct coupling

b.)Impedance coupling

c.) R C coupling

d.)Transformer coupling


A superconductor is a –

a.) A material showing perfect conductivity and Meissner effect below a critical temperature

b.) A conductor having zero resistance

c.) A perfect conductor with highest di-magnetic susceptibility

d.) A perfect conductor which becomes resistance when the current density through it exceeds a critical value


When an inductor tunes at 200 KHz with 624 pF capacitor and at 600 KHz with 60.4 pF capacitor then the self capacitance of the inductor would be –

a) 8.05 pF

b) 10.05pF

c.) 16.01pF

d.) 20.01pF


The Q of a radio coil –

a.) is independent of frequency

b.) increases monotonically as frequency increases

c.) decreases monotonically as frequency increases

d.) increases upto a certain frequency and then decreases beyond that frequency


When a generator of internal impedance and operating at 1GHz feeds a load via a coaxial line of characteristic impedance 50 ohm then the voltage wave ratio on the feed line is –

a.) 0.5

b.) 1.5

c.) 2.5

d.) 1.75


The coding system typically used in digital telemetry is –

a.) PPM (pulse position modulation)

b.) PAM (pulse amplitude modulation)

c.) PCM (pulse code modulation)

d.) PDM (pulse duration modulation)


Radiation pyrometers are used for the measurement of temperature in the range of –

a.) -2000C to 5000C

b.) 00C to 5000C

c.) 5000C to 12000C

d.) 12000C to 25000C


RF amplifier of an A.M. receiver is normally biased in –

a.) Class 'A'

b.) Class 'b'

c.) Class 'C'

d.) None


The value of gate voltage for the operation of enhancement of only N channel MOSFET has to be –

a.) High positive

b.) High negative

c.) Low positive

d.) Zero


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