﻿ DRDO Engineering Aptitude Papers and Interview Questions for All Engineering Branches Aptitude Papers For B.tech Students all Engineering Branches

DRDO EXAMINATION QUESTION PAPER YEAR 2009

Section – A

1. The thermal conductivity k of a liquid metal is predicted via the

empirical equation k = Aexp(B/T), where k is in Js-1m-1K-1 and T is absolute

temperature in K. A and B are constants. The units of A and B are, respectively,

(A) Js-1m-1K-1 and K-1 (B) Js-1m-1K-1 and K

(C) J-1 smK and K-1 (D) J-1 smK and K

2. % Excess air for combustion process is defined as(O2 entering the

process-O2 required)

(A) % Excess air = ——————————————— x 100 O2 required (O2 required –

O2 entering the process)

(B) % Excess air =————————————————– x 100 O2 entering the

process O2 required

(C) % Excess air =———————————————- x 100 (O2 entering the process

– O2 required) O2 entering the process

(D) % Excess air =——————————————————– x 100 (O2 required – O2

entering the process)

3. To prepare a solution of 50% sulfuric acid, a dilute waste acid

containing 27% sulfuric acid is fortified with a fresh acid containing 96%

sulfuric acid. The amount of fresh acid required for each 100 kg of dilute waste

acid is

(A) 13.5 kg (B) 25 kg (C) 50 kg (D) 100

kg

4. A flue gas analysis gave 10% O2, 25% CO2 and 65% N2 at 160 °C and 760 mm

Hg. The ratio of partial pressures of CO2 to O2 is equal to

(A) 1 (B) 2 (C) 2.5 (D) 4

5. In the extraction of nicotine from a nicotine-water solution by

kerosene, the pressure and temperature are kept constant. The available degree(s)

of freedom is/are

(A) 0 (B) 1 (C) 2 (D) 3

6. The hydrostatic equation of pressure P with height h of an

incompressible fluid of density ? and specific weight ? is

(A) P = ?/h (B) P = ? / h

(C) P = ? h (D) P = ? h

7. A gas is being compressed from an enthalpy of 489 kJ/kg to 509

kJ/kg in a steady state open process. The entry and exit velocities of the gas

are zero and 60 m/s, respectively. Assume that there is no heat loss or gain, no

reaction, and potential energy change is negligible. If the load is 100 kg/h of

gas, the work done on the gas is equal to

(A) 2000 kJ (B) 2180 kJ (C) 2500 kJ (D) 3000 kJ

8. The corresponding Maxwell relation for the Gibbsian equation dG =

-SdT +VdP is

(A) (B)

(C) (D)

Statement for Linked Answer – Questions 9 and 10:A system is taken from state A to state B along path ACB where 100 J of heat

flows into the system and the system does 40 J of work.

9. How much heat flows into the system along path AEB if the work

done by the system is 20 J?

(A) 20 J (B) 40 J (C) 60 J (D) 80 J

10. The system returns from B to A along path BDA. If the work done on

the system is 30 J, what will be the amount of heat liberated/generated?

(A) -90 J (B) 90 J (C) 30 J (D) -30 J

11. Acentric factor for Argon is

(A) >1 (B) 1 (C) 0 (D) < 1

12. Wet steam at 270 °C enters a throttling calorimeter with enthalpies

of 1200 kJ/kg and 2800 kJ/kg in liquid and gas phase, respectively. It leaves as

supersaturated steam at 0.1 MPa and 120 °C with an enthalpy of 2700 kJ/kg. The

quality of steam is

(A) 14/16 (B) 13/16 (C) 15/16 (D) 27/40

13. Superheated steam at 3 MPa and 300°C having enthalpy of 3000 kJ/kg

enters a turbine at the rate of 1 kg/sec and leaves as dry saturated steam at 60

°C with an enthalpy of 2600 kJ/kg. placementpapers.net If kinetic and potential energy changes are

ignored, the power output of the turbine is

(A) 400 kW (B) 5600 kW (C) 3000 kW (D) 2600 kW

Statement for Linked Answer – Questions 14 and 15: reversible heat engine absorbs 800 kJ as heat from a reservoir at 600 K and

rejects 100 kJ energy as heat to a reservoir at 300 K, as shown in the following

figure.

Q14. The heat interaction (Q) with reservoir at 400 K is

(A) – 600 kJ (B) 400 kJ (C) – 400 kJ (D) 600 kJ

15. The work done (W) by the engine is

(A) 500 kJ (B) 400 kJ (C) 350 kJ (D) 300 kJ

16. The partial volume of component A in a binary mixture (A – B) is 60

x 10-6 m3/mol. The mole% of A in the mixture is 60%. The density of the mixture

is 760 kg/m3. What will be the partial volume (m3/mol) of B in the mixture?

(placementpapers.netGiven: Molar mass of A is 50 x 10-3 kg/mol; molar mass of B is 20 x 10-3

kg/mol)

(A) 30 x 10-6 (B) 35 x 10-6 (C) 40 x 10-6 (D) 60 x 10-6

17. The enthalpy of vaporization of water at 100 °C is 2300 kJ/kg. The

isobaric heat capacities of liquid and vapor are, respectively, 4.0 kJ/kg-K and

2 kJ/kg-K. The enthalpy of vaporization at 150 °C will be

(A) 2400 kJ/kg (B) 2100 kJ/kg (C) 2500 kJ/kg

(D) 2200 kJ/kg

18. The following equations have been proposed for an isothermal binary

solution where the standard states are the pure components at the solution

temperature and pressure: ?1 = Ax1; ?2 = Bx2

What can be said about the above relation?

(A) It satisfies Gibbs-Duhem equation

(B) It does not satisfy Gibbs-Duhem equation

(C) It is thermodynamically consistent

(D) It satisfies both (A) and (C)

19. The enthalpy change of some reactions are given below:

CO (g) + O2 (g) ? CO2 (g) ?H = -300 kJ

H2 (g) + O2 (g) ? H2O (1) ?H = -320 kJ

H2O(1) H2O(g) ?H = 50 kJ

What will be the enthalpy change for the following reaction:

CO(g) + H2O(g) à CO2 (g) + H2 (g)

(A) -70 kJ (B) 30 kJ (C) -30 kJ (D) 70 kJ

20. The decrease in the Helmholtz Free Energy for system in a given

process for which initial and final temperatures are equal to the surrounding

temperature indicates.

(A) Maximum work obtained from the system

(B) Minimum work obtained from the system

(C) Minimum work which can be done on the system

(D) Both (A) and (C)

21. The vapor pressures of benzene and toluene at 70 °C are 4 and 6 atm,

respectively. A liquid feed of 0.6 moles of toluene at the same temperature is

vaporized. Assuming Raoult’s law, the vapor phase mole fraction of benzene at

equilibrium is approximately.

(A) 0.30 (B) 0.40 (C) 0.50 (D) 0.60

22. An oil film of viscosity u and thickness h is sheared between a

solid stationary wall and a circular disc of radius R, where h < < R. The

circular disc is rotating with angular speed w. For the same thickness of the

film, if the radius of the disc is doubled, the angular speed remaining the

same, by what factor the torque on the disc increases?

(A) 2 (B) 4 (C) 8 (D) 16

23. A circular fire hose of inner cross-sectional area 100 cm2 is

connected to a nozzle whose exit cross-sectional area is 4 cm2. The horizontal

nozzle is discharging water at 0.6 m3/minute to the atmosphere. If a pressure

gauge is connected to the hose side just before the nozzle, what would be the

reading of the pressure gauge?(Density of water = 1000 kg/m3 )

(A) 312 kPa (B) 624 kPa (C) 89 kPa (D) 178 kPa

24. A reciprocating pump has a piston of cross-sectional area A and is

connected to a crank of radius r which is rotating with angular velocity ?. The

pump is connected to the suction and the delivery pipes whose

placementpapers.net internal

cross-sectional area is A1. The maximum velocity of the fluid element in the

suction or delivery pipe is

(A) (B) (C) ?r (D)

25. Assuming that the thrust T of a propeller depends upon the diameter

D, speed of advance V, angular velocity ?, dynamic viscosity µ, and density ?,

which of the following dimensionless parameters can be derived by dimensionless

analysis?

(1) (2) (3) (4)

Select the correct answer using the codes given below:

(A) 1, 2 and 3 (B) 1, 3 and 4 (C) 2, 3 and 4 (D) 1, 2 and 4

26. The velocity profile u in the boundary layer over a flat plate is

given by . where U is the free stream velocity, y is the vertical distance of

the velocity point from the flat plate and d is the boundary layer thickness.

The displacement thickness of the boundary layer is

(A) (B) (C) (D)

27. Which of the following statements is INCORRECT about thixotropic

fluids?

(A) Apparent viscosity depends on the time of shearing

(B) Thixotropy is an irreversible process

(C) Thixotropic fluid shows shear thinning behavior

(D) Thixotropic fluids are in general non-Newtonian fluids.

28. A small liquid droplet of radius 1 mm and density 900 kg/m3 is rising up

in a column of water. What is the terminal rise velocity of the drop if creeping

flow conditions are assumed?(Given: viscosity of water = 1 cp, Gravitational

constant g = 10 m/s2 )

(A) m/s (B) m/s (C) m/s (D) m/s

29. Which of the following is NOT RECOMMENDED to increase the

collection efficiency of a cyclone separator?

(A) Increase in particle density

(B) Decrease in gas temperature

(C) Increase in particle diameter

(D) Increase in gas flow rate

Statement for Linked Answer – Questions 30 and 31: In a fluidized bed

operation, spherical particles of 1 mm diameter are packed to a height of 1.0

meter. The porosity of this bed is measured to be 0.4. At the minimum

placementpapers.net fluidization with air the bed height expands to 1.2 meter.

(Given: Particle density = 1200 kg/m3, Gravitational constant g = 10 m/s2 ).

30. The porosity of the bed at minimum fluidization is

(A) 0.4 (B) 0.3 (C) 0.5 (D) 0.6

31. The approximate value of pressure drop in the bed at minimum

fluidization will be

(A) 3600 N/m2 (B) 7200 N/m2 (C) 6000 N/m2 (D) 3000 N/m2

32. In a centrifugal filter the inside radius of the filter basket is

R2 and radius of the inner surface of liquid is R1. The centrifuge is rotating

with an angular speed ?. Which of the following is true about the pressure drop

?P from the centrifugal action?

(A) ?P µ ?1/2 (B) ?P µ (R22 + R12)

(C) ?P µ (R22 – R12) (D) ?P µ ?

33. In a dry crushing operation the mean diameter of the feed and

product particles are 100 mm and 1 mm, respectively. The sphericity of the feed

and product particles are 0.5 and 1.0, respectively. If the feed particles of

200 mm diameter with the same sphericity are handled at the same feed rate, what

will be the percentage increase in power requirement assuming that the product

remains the same?

(A) (B) (C) (D)

34. Which of the following is INCORRECT about the boundary layer

development over flat infinite plate?

(A) The fluid velocity at solid-liquid interface is zero

(B) The shear rate inside the boundary layer is not zero

(C) The boundary layer thickness increases with distance from the leading

edge

(D) The flow in the boundary layer close to the leading edge is turbulent

35. Which of the following velocity field represents an irrotational

flow for x, y > 0, x ? y?

(A) V = 2 yi – 2x .j

(B) V = 2 xi – 3y,j

(C) V = xy i – xy j

(D) V = xy i + xy j

36. In a laminar flow between two parallel plates separated by a

distance H, the head loss varies

(A) directly as H (B) inversely as H2

(C) directly as H2 (D) inversely as H3

37. Two viscous liquids are to be blended by passing through a pipe.

Which of the following would be the most suitable condition for axial mixing?

(A) Creeping flow (B) Low Reynolds number

flow

(C) High Reynolds number flow (D) Plug flow

38. A U-tube manometer measures

(A) absolute pressure at a point

(B) local atmospheric pressure at a point

(C) difference in total energy between two points

(D) difference in pressure between two points

39. What will happen to the heat loss if foam insulation, with thermal

conductivity 0.09 W/m-K is added to a 5 cm outer diameter pipe carrying hot

water? (Heat transfer coefficient on the outer surface = 10 W/m2-K)

(A) Increases (B)

Decreases

(C) First increases then decreases (D) Remains

constant

40. Biot number (hL/k) is important for which mode of heat transfer?

(A) Natural convection (B) Forced convection

(C) Transient heat conduction (D) Radiation

41. The temperature distribution in a 0.25 m thick wall is given as

T (°C) = 250 + bx – cx2, where x (in meter) is the position of a point with

respect to the surface of the wall which is at higher temperature. The thermal

conductivity of the wall is 5.95 W/m-°C. What will be the value of b if the

surface at x = 0 is insulated?

(A) 0 (B) 1 (C) – 1 (D) 0.5

42. When momentum diffusivity is greater than the thermal diffusivity,

the velocity boundary layer

(A) develops faster than the thermal boundary layer

(B) develops slower than the thermal boundary layer

(C) grows together

(D) disappears

43. An aluminium ball of area 0.5 m2 and mass 10 kg is cooled in

ambient at 25 °C. When the temperature of the ball is 125 °C, it is found to

cool at the rate of 6 °C/min. What will be the surface heat transfer

coefficient? placementpapers.net(Given, Cp = 0.5 kJ/kg-°C)

(A) 0.5 W/m2-°C (B) 0.01 W/m2-°C

(C) 0.05 W/m2-°C (D) 0.l W/m2-°C

44. Water at 25 °C enters a pipe with internal diameter 2 cm having a

constant wall heat flux of 1 KW/m2. The flow is hydro dynamically and thermally

fully developed. What will be the difference between the local wall temperature

and the local mean (bulk) temperature? (Thermal conductivity of pipe = 0.4

W/m-°C; Nusselt Number = 5.0)

(A) 5 °C (B) 15 °C (C) 10 °C (D) 50 °C

45. When some liquid nitrogen spills on the floor of a laboratory, the

droplets move so briskly that they appear to be dancing before they disappear.

This phenomenon

(A) is related to pool boiling (B) is related

to film boiling

(C) is related to nucleate boiling (D) has nothing

to do with boiling

46. Consider sphere 1 enclosed by sphere 2 as shown in the following

figure. The area of sphere 2 is double the area of sphere 1. What are the

various view factors (F1I, F12, F21, F22)?

(A) 0, 0.5, 0.5, 1 (B)

0.5, 1, 1, 0.5

(C) 0.5, 0.5, 0, 1 (D) 0, 1,

0.5, 0.5

47. A triple-effect evaporator is concentrating a liquid that has no

appreciable elevation in boiling point. The temperature of the steam to the

first effect is 110 °C and the boiling point of the solution in the last effect

is 50 °C. The ratio of the heat transfer resistance of the first effect to that

of the overall heat transfer resistance is 0.2. At what temperature will the

liquid boil in the first effect?

(A) 95 °C (B) 98 °C (C) 90 °C (D) 92 °C

48. Gas A is being cracked on a catalyst as per the reaction, A?2B+C in

such a way that A diffuses to the cracking surface and B diffuses back, while C

is not diffusing. At steady state what will be the ratio of molar flux of A to

the total molar flux?

(A) 1/3 (B) –1 (C) 2 (D) 2/3

49. The eddy momentum diffusivity, the thermal diffusivity and the mass

diffusivity will be same for most of the gases when

(A) both Prandtl and Schmidt numbers are equal to 1.2

(B) both Prandtl and Schmidt numbers are equal to 10.0

(C) both Prandtl and Schmidt numbers are equal to 0.1

(D) both Prandtl and Schmidt numbers are equal to 1.0

50. According to surface renewal theory, the average mass transfer

coefficient is directly proportional to

(A) DAB (B) (C) (D)

51. For the flow of a fluid at right angles to a circular cylinder, the

average heat transfer coefficient around the periphery is given by Nu = a + b

Re”‘ Pr”, where, Nu is Nusselt Number, Sh is Sherwood Number, Pr is Prandtl

Number, Sc is Schmidt Number and a, b, m, n are constants. The analogous

expression for the mass transfer can be expressed as

(A) Sh = a + b Re”‘ Sc” (B) Sh = b + a Re”‘ Sc”

(C) Nu = m + n Re” Scb (D) Nu = n + m Re” Scv

Statement for Linked Answer – Questions 52 and 53: A horizontal spray chamber with recirculated water is used for adiabatic

humidification and cooling of air. Air with humidity of 0.01 kg water per kg of

dry air is entering the unit with a flow rate of 2 kg/m2-s. The humidity of exit

stream is 0.02 kg water per kg of dry air. The active part of the chamber is 1.0

m long. placementpapers.net The humidity at the saturated condition is 0.03 kg water per kg of dry

air.

52. The volumetric gas phase mass transfer coefficient in kg/m3-s in

the operation is equal to

(A) ln 2 (B) ln 3 (C) ln 4 (D) ln 5

53. If a duplicate spray chamber operating in the same manner were to

be added in series with the existing chamber, the expected humidity of the

outlet air in kg water per kg of dry air is equal to

(A) 0.03 (B) 0.02 (C) 0.025 (D) 0.05

54. A saturated liquid mixture with 50% (mole basis) of more volatile

component is to be separated in a continuous distillation column. The mole% of

more volatile component in the distillate is 90. The constant relative

volatility of more volatile component is 1.5. Assuming McCabe-Thiele method, the

minimum reflux ratio for this operation is

(A) 3 (B) 2 (C) 2.5 (D) 1

55. In a perfectly mixed flow model, the ratio of the Murphree plate

efficiency to the point efficiency is equal to

(A) 0 (B) 1 (C) < 1 (D) > 1

Statement for Linked Answer – Questions 56 and 57: A waste stream of organic vapor in a gas from a process was adsorbed by solid

particles in packed bed of length 20 cm. The breakpoint concentration is set at

C/C0 = 0.10 and the breakpoint time is 4 hours.

56. What will be the time equivalent to the unusable capacity of the

bed up to the breakpoint time?

(A) 3 hours (B) 1.5 hours (C) 4 hours (D) 3.6

hours

57. The stoichiometric capacity of the bed is 7.2 hours. What will be

the length of unused bed for this operation?

(A) 7.2 cm (B) 20 cm (C) 10 cm (D) 4 cm

58. In liquid-liquid extraction, the solvent B is used to separate

solute C from a given solution of A and C. If A and B are completely insoluble

in one another, the selectivity of B will be

(A) 8 (B) 0 (C) < 0 (D) 1

59. A batch of wet solid is to be dried from 80% to 50% moisture (wet

basis). The drying surface is 1 m2/10 kg of dried solid. The drying takes place

within the constant rate period. The constant flux of drying is 0.3 x 10-3

kg/m2-s. The drying time is

(A) 102 s (B) 103 s (C) 104 s (D) 105 s

60. A gas with a flow rate of 25 mol/m2.s is scrubbed by a pure liquid

to remove a component in a counter-current packed bed column. The specific

interfacial area of the packing material is 1 m-1. The individual gas-film mass

transfer coefficient is 25 mol/m2.s. If the overall mass transfer resistance is

50% of the individual gas-film mass transfer resistance, the overall height of

gas phase transfer unit (HTU)og is

(A) 0.5 m (B) 1.0 m (C) 2.0 m (D) 2.5 m

61. If L is the liquid flow rate. G is the gas flow rate and m is the

slope of the equilibrium line, the absorption factor is

(A) mL / G (B) G / mL (C) L / mG (D) LG / m

62. A vessel dispersion number of zero indicates

(A) plug flow behavior (B) mixed flow behavior

(C) batch reactor behavior (D) both (B) and (C)

64. A first order reaction takes place in a single cylindrical pore

having strong diffusion resistance. For a particle size (R), the rate of the

reaction varies

(A) directly with R

(B) directly with vR

(C) inversely with ­vR

(D) inversely with R

65. The response curve for a step input signal from a reactor is called

C curve. The variance of C curve in a `tank in series model’ comprising of `n’

tanks is

(A) n (B) 1/n (C) n0.5 (D) n2

66. Calculate the weight of the catalyst required for the 75%

conversion of sample A (CAO = 8 mol/m3) in a mixed flow reactor at a flow rate

of 1000 mole/min.

(The weight time of the operation is 4.15 kg s/m3)

(A) 500 kg (B) 519 kg (C) 525 kg (D) 600 kg

67. In an endothermic reaction, for an increase in temperature, the

equilibrium conversion

(A) rises (B) falls

(C) remains constant (D) first increases then

decreases

Statement for Linked Answer – Questions 68 and 69: placementpapers.net Aqueous phase decomposition of A is investigated in two mixed flow reactors

in series. The second reactor is having twice the volume of the first reactor.

At steady state with a feed of 1 mole/litre and mean residence time of 96

seconds in first reactor, the concentration of A in the first reactor is 0.5

mol/litre and in the second 0.25 mol/litre.

68. The order of the reaction is

(A) 1 (B) 2 (C) 0 (D) 3

69. The rate constant (lit/mol-min) is

(A) 1.5 (B) 3 (C) 2 (D) 1.25

70. For a zero order reaction in a varying volume batch reactor, the

correct equation is

72. For a particular reaction where order of the reaction is less than

one, the CORRECT sequence of reactors for efficient use is

(A) Small MFR, Large MFR, PFR (B) Large MFR, Small MFR,

PFR

(C) PFR, Large MFR. Small MFR (D) PFR, Small MFR, Large

MFR

73. The half-life period of the reaction A ? products is independent of

the initial concentration of the reactant A if the order of the reaction is

(A) 0 (B) 1 (C) 2 (D) 1/2

Statement for Linked Answer – Questions 74 and 75: Chemical A reacts to form R (k1 = 8 hr-1) and chemical R reacts to form S (k2

= 3 hr-1). In addition R slowly decomposes to form T (k3 = 1 hr-1). A solution

containing 1 mol/litre of A is introduced into a batch reactor.

74. What is the maximum concentration of R (mol/lit)?

(A) 0.5 (B) 0.25 (C) 0.75 (D) 1.0

75. How long will it take (in hours) for R to reach its maximum

concentration?

(A) ln 2 (B) ln 2 (C) ln 2 (D) 2 1n 2

76. Ordinary mercury-in-glass thermometer (without any covering or air

gap) is an example of

(A) zero-order system (B) first-order system

(C)second-order system (D) third-order system

77. The symbol of the type __________ denotes

(A) Pneumatic line (B) Fluid pressure line

(C) Electrical line (D) Software link

78. The Laplace transform of sin (kt) is

(A) k /(s2 + k2) (B) s /(s2 + k2)

(C) k /(s2 – k2) (D) s /(s2 – k2)

79. A control system is unstable if the open loop frequency response

exhibits an amplitude ratio exceeding unity at the cross-over frequency. This is

(A) Bode stability criteria (B) Routh stability criteria

(C) Nyquist criteria (D) Root-locus criteria

80. What will be the maximum value of K(such that a closed loop system

having the following characteristic equation is stable ?

s3 + 6s2 + 11s + 6 (1+KC) = 0

(A) KC < 10 (B) KC < 15 (C) KC <

(D) KC <

81. The transfer function of a proportional-integral-derivative (PID)

controller is

(A) = KC (1 + tD S + tD S) (B) = KC + tD + tD S

(C) = KC (D) =

82. For the block diagram shown below what will be the overall transfer

function for the change in set point (U = 0)?

(A) = (B) =

|(C) = (D) =

83. The amplitude ratio (AR) for the sinusoidal response of a

first-order system is always

(A) <1 (B) >1 (C) 1 (D) 0

84. Solenoid valve works like

(A) Proportional controller (B) PD controller

(C) PID controller (D) On-off controller

85. The final product from a chemical plant is composed of two

materials A and B with some of each being required. The total cost per unit of

the finished product is CT = Rupees/unit. If the amount of A is fixed, the

amount of B required for minimum total cost of product is

(A) (B) (C) A/36 (D) 720A

86. Which of the following is NOT a function of baffle in the

shell-and-tube heat exchanger?

(A) Direct the flow across the tube bundle

(B} Support the tube from sagging

(C) Arrest the vibration of the tubes

(D) Decrease the turbulence of the fluid

87. Match the following:

(1) Microfiltration (P) Solution/diffusion

(2) Reverse Osmosis (Q) Size exclusion

(3) Distillation (R) Vapor/liquid

equilibria

(4) Stripping (S) Absorption

(A) 1-P, 2-Q, 3-R. 4-S (B) 1-Q, 2-P, 3-R, 4-S

(C) 1-S, 2-R, 3-P, 4-Q (D) 1-R, 2-Q, 3-S, 4-P

88. What is the cross-flow area in the case of a shell-and-tube heat

exchanger where inside diameter of the shell is 5 m, baffle spacing 0.5 m,

clearance between the tubes 5 cm, outside diameter of the tube 10 cm and pitch

of the tube 2 cm?

(A) 12.5 m2 (B) 6.25 m2 (C) 22.5 m2 (D) 10 m2

89. A chemical company has purchased leaf pressure filters with 100 ft2

for purifying an inorganic liquid stream at the cost of Rs. 15000. In a similar

application the company will need 900 ft2 leaf pressure filter.

placementpapers.net The size

exponent of this type of filter is 0.5. The purchased price of the 900 ft2

filter will be

(A) Rs.135000 (B) Rs. 67500 (C) Rs. 45000

(D) Rs. 90000

90. Which of the following results in book values greater than those

obtained with the straight line method?

(A) Declining balance method (B) Sum-of-the

years digit method

(C) Multiple straight line method (D) Sinking fund

method

91. The Darcy’s law is used to calculate

(A)heat transfer coefficient

(B)friction factor in pipe flow

(C)permeability of porous medium

(D) vapor pressure in azeotropic mixtures

92. `Total capital investment’ for a chemical process plant comprises

of the fixed capital investment and the

(A) working capital (B) indirect production costs

(C) direct production costs (D) overhead costs

93. Which of the following statements is INCORRECT for the manufacture

of sulfuric acid by contact process?

(A) Yield is higher than the chamber process

(B) Catalyst used is vanadium pentoxide on a porous carrier

(C) Final scrubbing is done using concentrated sulfuric acid only

(D) Optimization of space velocity in catalyst chamber is a major

engineering problem.

94. Match the following:

(1) Paper (P) Zeigler

(2) Soda ash (Q) Sachsse

(3) Polyethylene (R) Kraft

(4) Acetylene (S) Solvay

(A) 1-P, 2-R, 3-Q, 4-S (B) 1-P, 2-Q, 3-R, 4-S

(C) 1-S, 2-R, 3-Q, 4-P (D) 1-R, 2-S, 3-P, 4-Q

95. Match the following:

(1) Maleic anhydride (P) Ag0

(2) DDT (Q) NH3

(3) Ethylene oxide (R) V205

(4) Soda ash (S) Oleum

(A) 1-R, 2-S, 3-P, 4-Q (B) 1-S, 2-R, 3-Q, 4-P

(C) 1-R, 2-S, 3-Q, 4-P (D) 1-P, 2-Q, 3-R, 4-S

96. Match the following:

(2) Margarine (Q) Pesticide

(3) Litharge (R) Enzyme

(4) Lipase (S) Fat

(A) 1-S, 2-P, 3-Q, 4-R (B) 1-S, 2-R, 3-Q, 4-P

(C) 1-Q, 2-S, 3-P, 4-R (D) 1-R, 2-S, 3-P, 4-Q

97. Cetane number of diesel is the measure of its

(A) smoke point (B) ignition delay

(C) viscosity (D) oxidation stability

98. Choose the CORRECT statement from the following:

(A) Aromatics have lowest octane number

(B) Paraffins are the hardest to crack

(C) Dearomatisation of kerosene increases its smoke point

(D) Aniline point is a property of LPG

99. Choose the INCORRECT statement from the following:

(A) SBR compared to natural rubber has poor tensile strength

(B) Silicone is an inorganic polymer

(C) Nylon-6 is a polyamide

(D) Neoprene is an elastomer

100. Match the following:

(1) Permanent hardness of water (P)Steam distillation

(2) Alkyl group of detergent(Q)Cation/anion

exchanger

(3) Rancidity of oil (R)Hydrogenation

(4) Essential oil(S)Hydrophobic

(A) 1-Q, 2-S, 3-R, 4-P (B)

1-Q, 2-R, 3-S, 4-P

(C) 1-R, 2-P, 3-Q, 4-S (D) 1-S, 2-P,

3-R, 4-Q

DRDO Placement Paper (Interview Question)

Sample Interview Question:

1) Coldest planet: Ans:- Pluto

2) INS Shivali is the first:

3) Which one of the following was NOT indegineously developed?:Prithvi/Akash/Agni

4) Full form of SARS

5) Anthrax is a :Virus/Bacteria

6) Dakshina Gangothri is:Ganga's origin/Indian camp @ antartica/.../...

7) Which of the following is a chemical weapon:Mustard Gas/Marsh Gas/.../...

8) A question based on Coding and Decoding

9) Another question similar to above

10) Question on series completion

11) Another series completion question

12) Where is Institute of Forensic Science?: Ans:-Hyderabad

13) A G.K question based on X and Y chromosomes in males and females

DRDO Placement Paper of WrittenTest 2006

1) If 100ns is Memory Access Time & 125 microsecond is 1frame period. The no. of line that can be supported in a Time Division Switch is

a)125 Lines

b)625 Lines

c)525 Lines

d)465 Lines

2)The no. of edjes in disjoint Hamilton circuit in a complex graph with 17 edges is

a) 8

b) 9

c) 136

d) 17^2

3) 15 persons in a club sit every day in dinner table such that every member has different neighbor. This arrangement will last for how many days.

4) Assume a system has 16MB cache mean Disk Access Time & cache Access time is 76.5 ns & 1.5 overall mean Access time us 465ms for each tripling the memory the miss rate is halved. The memory required to bring down the mean Access time to 24ns is

a) 16 MB

b) 24 MB

c) 32 MB

d) 48 MB

5) Average transfer speed of a i/p serial line is minimum 25,000 Bytes & maximum 60000 Bytes. Polling Strategy adopted takes 4microsec (whether there is any i/p byte or not). It is assured that byte that retrieved from controller before next byte arrives is lost. Then the maximum safe polling interval is

a) 12

b) 12.33

c) 12.67

d) 32

6) A hard disk has a rotation speed of 4500RPM. then the latency time is

a) .4

b) .6

c) .7

d) .9

7) Suppose all elements above the principal diagonal od n x n matrix A are zero. If non zero elements of the lower triangular Matrix is stored in an array B with A[1][1] stored at B[1]. The addressing formula to the nonzero element in A[i][j]=?

a) A[i][j]

b) i(j-1)/2 +i

c) j(i-1)/2 +i

d) i(i-1)/2 +j

8) The minimum number of comparisons required to find the second smallest element in a 1000 element array is

a) 1008

b) 1010

c) 1999

d) 2000

9) The internal path length of a Binary Tree with 10nodes is 25. The external path length is

a) 25

b) 35

c) 40

d) 45

10) Average No. of Comparisons required to sort 3 elements is

a) 2

b) 2.33

c) 2.67

d) 3

11) In a switch the mean arrival rate of packets is 800 Packets/sec and the the mean service rate is 925 Packets/sec

a) .008 Sec

b) .08 sec

c) .8 sec

d) 1.1 sec

12) What is Interface Control Information?

13) The minimum no. of Multiplications needed to compute x^768 is

a) 9

b) 10

c) 425

d) 767

14) Find values for a,b,c,d

c 1 1 1

0 a 1 b

_______

1 0 d 015)(967)basex = 321base9

PART II General 50 General Non-Technical [4 Options]

More than 20 questions were from Mathematics.

1) where the Mars Rover Landed?

2) In Which Day world Telecom Day Celebrated?

3) Laser is used for what?

a) Treatment of Cancer

b) Treatment of Eyes

c) Treatment of Heart

d) Treatment of Kidney

4) Which country is not a Member of SAARC

b) Myanmar

c) Maldives

d) Nepal

5) The New Biotechnology Software introduced by TCS is?

6) What is Wi Fi?

7) Which is the fastest Cruise Missile?