16
www.gradeup.co 1 | Page 1. A motor is driving a solid circular steel shaft transmits 40kW of power at 500 rpm. If the diameter of the shaft is 40 mm, The maximum shear stress in the shaft is ____ MPa. A. 60.7 B. 50.5 C. 55.25 D. 51.36 Answer ||| A Solution ||| P=40kW N=500rpm D=40mm T= 3 16T d 60, 000 40 60, 000 2 2 500 763.94 P T N N m 3 3 16 763.94 10 40 60.79MPa 2. Consider the following partial differential equation for u(x,y) with the constant 1: 0 u u c c y X Solution of this equation is A. u(x,y)=f(x+cy) B. u(x,y)=f(x-cy) C. u(x,y)=f(cx+y) D. u(x,y)=f(cx-y) Answer ||| B Solution ||| Given 0 u u c y X '( ) ' 0 , ( ) u f x cy y u cf x cy y u u y y uxy fx cy 3. The following figure shows the velocity-time plot for a particle travelling along a straight line. The distance covered by the particle from t=0 to t=5s is ______ m. A. 13 B. 12 C. 15 D. 10 Answer ||| D Solution ||| Area under V - T wave 1 2 3 4 5 1 1 4 1 1 11 1 2 2 4 2 2 2 0.5 1 2.5 6 10 S a a a a a m 4. The damping ratio for a viscously damped spring mss system, governed by the relationship 2 2 ( ), dx dx m C kx Ft dt dt is given by A. c mk B. 2 c km C. c km D. 2 c mk Answer ||| B Solution ||| 2 2 ( ); 2 x c dx dx m c k Ft dt dt c c c km 5. The differential equation 2 2 16 0 dy y dx for y(x) with the two boundary conditions 0 2 1 1 x x x dy dy and dx dx has A. no solution B. exactly two solution C. exactly one solution D. infinitely many solutions Answer ||| A Solution ||| 2 2 16 0 dy y dx 0 1 x dy dx 2 1 x x dy dx

S a a a a a ª º § ·ª º 1 1 4 ¬ ¼ © ¹¬¼ 22... 2 | P a g e 2 16 0 04 m mi r 22 12 12 2 2 2 2 1 cos4 sin cos4 sin sin4 4 cos 4 0 4 '( ) 4 4 1 '(0) 1 0 4 1 4 1 ' 1 0 4 1 24

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Page 1: S a a a a a ª º § ·ª º 1 1 4 ¬ ¼ © ¹¬¼ 22... 2 | P a g e 2 16 0 04 m mi r 22 12 12 2 2 2 2 1 cos4 sin cos4 sin sin4 4 cos 4 0 4 '( ) 4 4 1 '(0) 1 0 4 1 4 1 ' 1 0 4 1 24

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1 | P a g e

1. A motor is driving a solid circular steel shaft transmits 40kW of power at 500 rpm. If the diameter of the shaft is 40 mm, The maximum shear stress in the shaft is ____

MPa.

A. 60.7 B. 50.5 C. 55.25 D. 51.36 Answer ||| A Solution ||| P=40kW N=500rpm

D=40mm

T=3

16T

d

60,000 40 60,000

2 2 500

763.94

PT

N

N m

3

3

16 763.94 10

40

60.79MPa

2. Consider the following partial differential equation for

u(x,y) with the constant 1: 0u u

c cy X

Solution of this equation is A. u(x,y)=f(x+cy) B. u(x,y)=f(x-cy) C. u(x,y)=f(cx+y) D. u(x,y)=f(cx-y) Answer ||| B

Solution ||| Given 0u uc

y X

'( )

'

0

, ( )

uf x cy

y

ucf x cy

y

u u

y y

u x y f x cy

3. The following figure shows the velocity-time plot for a particle travelling along a straight line. The distance covered by the particle from t=0 to t=5s is ______ m.

A. 13 B. 12 C. 15

D. 10

Answer ||| D Solution ||| Area under V - T wave

1 2 3 4 5

1 1 41 1 1 1 1

2 2

4 22

2

0.5 1 2.5 6

10

S a a a a a

m

4. The damping ratio for a viscously damped spring mss system, governed by the relationship

2

2( ),

d x dxm C kx F tdt dt

is given by

A. c

mk B.

2

c

km

C. c

km D.

2

c

mk

Answer ||| B Solution |||

2

2( );

2

x

c

dx dxm c k F tdt dt

c c

c km

5. The differential equation

2

216 0

d yy

dx for y(x) with

the two boundary conditions

02

1 1x

x x

dy dyand

dx dx

has

A. no solution B. exactly two solution C. exactly one solution

D. infinitely many solutions Answer ||| A

Solution |||

2

216 0

d yy

dx

0

1x

dy

dx

2

1x

x

dy

dx

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2 | P a g e

2 16 0

0 4

m

m i

1 2

1 2

2

2

2

2

1

2 2

cos 4 sin

cos 4 sin

sin 4 4 cos

4     0

4

'( ) 4 4

1'(0) 1 0 4 1

4

1' 1 0 4 1

2 4

1 1       

4 4

pc xand y

y x

y x x

y c c

y c c

c and bothnot poss

y c x c

c x c

c x c

ible

Hence there is no solution

6. Metric thread of 0.8 mm pitch is to be cut on a lathe.

Pitch of the lead screw is 1.5 mm. If the spindle rotates at 1500 rpm, the speed of rotation of the lead screw (rpm) will be ________ A. 650 B. 700 C. 750 D. 800

Answer ||| D Solution ||| Speed of rotation of lead screw

1500 0.8800

1.5rpm

7. The molar specific heat at constant volume of an ideal gas is equal to 2.5 times the universal gas constant

(8.314 J/mol.K). When the temperature increases by 100k, the change in molar specific enthalpy is ___ J/mol. A. 2809.2 B. 2909.9 C. 3010.2 D. 3101.9 Answer ||| B

Solution ||| 2.5 ( 8.314 / . )v v vC R where R J mol K

100

?

3.5

, 3.5 8.314 100

2909.9 /

p

p v v

p v

T K

H

H C T

C C R

C R

So H

H J mol

8. A particle of unit mass is moving on a plane. Its trajectory, in polar coordinates, is given by

2( ) , ( ) ,r t t t t where t is time. The kinetic energy of

the particle at time t=2 is A. 4 B. 12

C. 16

D. 24 Answer ||| C Solution |||

2

2

2

2

2

  2sec

1

ˆ ˆˆ ˆ( ) 1( ) 2

ˆ ˆ( ) 2 ( )

 

,

1

2

ˆ ˆ4( ) 4( )

16 16

32

1 1. . 1 32

.

2

?2

162

at t

m kg

drV r t r t t tr

dt

V t t t r

at t s

V t r

V

V

K E

r t t

K E

v

mv

m

9. The poisson’s ratio for a perfectly incompressible linear material is A. 1 B. 0.5 C. 0 D. infinity Answer ||| B

Solution ||| The poisson’s ratio for a perfectly incompressible linear material is Maximum i.e 0.5

10. A heat pump absorbs 10kW of heat from outside environment at 250 K while absorbing 15 kW of work. It delivers the heat to a room that must be kept warm at 300K. The coefficient of Performance (COP) of the heat

pump is _________. A. 1.66 B. 2.56 C. 3.35 D. 2.89 Answer ||| A

Solution |||

/

251.66

15

H

i p

QCOP

W

11. Which one of the following is NOT a rotating machine? A. Centrifugal pump B. Gear pump C. Jet pump D. Vane pump

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3 | P a g e

Answer ||| C Solution ||| In the given options all the pumps have rotating machine elements except Jet pump.

12. Consider the schematic of a riveted lap joint subjected to tensile load F, as shown below. Let d be the

diameter of the rivets, and fS be the maximum

permissible tensile stress in the plates. What should be the minimum value for the thickness of the plates to guard against tensile failure of the plates? Assume the

plates to be identical.

A. ( 2 )f

F

S W d

B.

f

F

S W

C. ( )f

F

S W d

D. 2

f

F

S W

Answer ||| A

Solution ||| f

FS

A

;( 2 )

( 2 )

f

f

FS

t W d

FtS W d

13. Water (density =1000 kg/m3) at ambient

temperature flows through a horizontal pipe of uniform cross section at the rate of 1 kg/s. If the pressure drop

across the pipe is 100 kPa, the minimum power required to pump the water across the pipe, in watts, is _______ A. 100 B. 125 C. 150

D. 200 Answer ||| A Solution ||| given,

31000 /

1 /

10

w kg m

m kg s

P kPa

So, minimum power require

1 100 1000

1000

100

fm gh

Pm g

g

Watts

14. For steady flow of a viscous incompressible fluid through a circular pipe of constant diameter, the average velocity in the fully developed region is constant. Which one of the following statements about the average velocity in the developing region is TRUE? A. It increases until the flow is fully developed.

B. It is constant and is equal to the average velocity in the fully developed region. C. It decreases until the flow is fully developed. D. It is constant but always lower than the average velocity in the fully developed region. Answer ||| B

Solution ||| The average velocity in pipe flow always be same either for developing flow or fully developed flow. 15. Cylindrical pins of diameter 15+0.020 mm are being produced on a machine. Statistical quality control tests show a mean of 14.995 mm and standard deviation of

0.004mm. The process capability index pC is

A. 0.833 B. 1.667 C. 3.333

D. 3.750 Answer ||| B

Solution ||| 6

p

USL LSLC

15.02 14.98

6 0.004

1.666

16. The product of Eigen values of the matrix P is

2 0 1

4 3 3

0 2 1

P

A. -6 B. 2 C. 6 D. -2

Answer ||| B

Solution |||

2 0 1

4 3 3

0 2 1

P

We know that, product of eigen values of P =

determinant of 2(3 6) 0 1(8) 6 8 2P

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4 | P a g e

17. Match the processes with their characteristics.

A. P – 2, Q – 3, R – 1, S – 4 B. P – 3, Q – 2, R – 1, S – 4 C. P – 3, Q – 2, R – 4, S – 1 D. P – 2, Q – 4, R – 3, S – 1 Answer ||| A

Solution ||| Electrical Discharge machining- Machining of electrically conductive materials

Ultrasonic machining- Machining of glass

Chemical machining- No residual stress

Ion Beam Machining- Nano-machining

18. The Value of

3

0

sin( )limx

x xis

x

A. 0

B. 3

C. 1

D. -1

Answer ||| D

Solution |||

19. In an arc welding process, welding speed is doubled. Assuming all other process parameters to be constant, the cross sectional area of the weld bead will

A. Increase by 25%

B. Increase by 50%

C. Reduce by 25%

D. Reduce by 50%

Answer ||| D

Solution ||| . .mV I H AV

2 1

1 2

12

1

2

2

AV

A V V

A V V

AA

By doubling welding speed, Area reduces by 50%

20. A six-face fair dice is rolled a large number of times.

The mean value of the outcomes is ______.

A. 3.5

B. 4.75

C. 5.25

D. 6.00

Answer ||| A

Solution ||| The Probabilities corresponding to the outcomes are given below:

( ) . ( )

1 1 1 1 1 11 2 3 4 5 66 6 6 6 6 6

11 2 3 4 5 6

6

21

6

3.5

mean E x x P x

21. Consider the two dimensional velocity field given by

where

1 1 2 2 , ,  ab nda ba are constant. Which one of the following

conditions needs to be satisfied for the flow to be incompressible?

A. 1 1 0a b

B. 1 2 0a b

C. 2 2 0a b

D. 2 1 0a b

Answer ||| B

Solution ||| Given

22. Consider a beam with circular cross-section of diameter d. The ratio of the second moment of area about the neutral axis to the section modulus of the area is.

A. 2

d

B. 2

d

C. d

D. d

Answer ||| A

Solution ||| 1

Zy

4

3

1 64

2

32

dd

yZ

d

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5 | P a g e

23. Saturated steam at 100°C condenses on the outside of a tube. Cold fluid enters the tube at 20° C and exists at 50°C. The value of the Log Mean Temperature

Difference (LMTD) is ________°C.

A. 55.76

B. 58.46

C. 63.82

D. 69.33

Answer ||| C

Solution |||

24. In a metal forming operation when the material has just started yielding, the principal stresses are

1 2 3180 , 100 , 0.MPa MPa Following Von

Mises criterion, the yield stress is ________ MPa.

A. 245.76

B. 240.12

C. 248.57

D. 251.98

Answer ||| A

Solution ||| As per Von-Mises criteria

2 2 2 2

1 2 1 3 5 1

2 2 2 2

2

180 100 100 0 0 180 2

245.76

m

m

m MPa

25. In the engineering stress-strain curve for mild steel, the Ultimate Tensile Strength (UTS) refers to

A. Yield stress

B. Proportional limit

C. Maximum stress

D. Fracture stress.

Answer ||| C

Solution ||| Ultimate tensile strength (UTS) is the maximum stress that a material can withstand while being stretched or pulled. UTS is the final amount of stress sustained in a tensile test at the exact moment the

object ruptures

26. A parametric curve defined by

cos , sin2 2

u ux y

in the range 0 1u is

rotated about the –axis by 360 degrees. Area of the surface generated is.

A. 2

B.

C. 2

D. 4

Answer ||| C Solution |||

Given cos , sin 0 12 2

u ux y

sin2 2

cos2 2

dx u

d

dx u

dy

We know that surface area when the curve revolved

about X- axis of a parametric curve is

2 21

0

2 21

0

2

2 sin sin cos2 2 2 2 2

dx dyy du

du du

u u udu

1 2

0

1

0

1

2

2

2 sin2 4

2 sin2 2

1cos2

2

2cos cos0

2

2 cos0 1

2

udu

udx

u

27. Assume that the surface roughness profile is triangular as shown schematically in the figure. If the

peak to valley height is 20 ,m The central line average

surface roughness   )(a nR i m is

A. 5 B. 6.67 C. 10 D. 20

Answer ||| A

Solution ||| max 20

54 4

a

RR m

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6 | P a g e

28. A thin uniform rigid bar of length L and mass M is

hinged at point O, located at a distance of3

L from one of

its ends. The bar is further supported using springs, each

of stiffness k, located at the two ends. A particle of mass

4

Mm is fixed at one end of the bar, as shown in the

figure. For small rotations of the bar about O, the natural frequency of the systems is.

A. 5k

M B.

5

2

k

M

C. 5k

M D.

5k

M

Answer ||| B Solution ||| Max moment of inertia of Rod.

2

0

22

0

2 2

0

2

0

2

12 3 2

12 36

9

cI I mr

ML L LI M

ML MLI

MLI

Mass moment of inertia of particular mass 2 2

2 2 2

2

4 3 9

2( )

9 9 9

particular

Total

M L MLI

ML ML MLI

0

2 2

2

2

0

2 20

3 3 3 3

2 50

9 9

5.

59

2 2

9

n

M

L L L LK K I

ML LK

Lk

k

ML M

29. A point mass of 100 kg is dropped onto a massless

elastic bar (cross-sectional area 2100 ,mm length =

1m, Young’s moduls = 100 GPa) from a height H of

10mm as shown (Figure is not to scale). If2 10 /g m s

, the maximum compression of the elastic bar is _______ mm.

A. 2.5 B. 3.3 C. 1.5 D. 0.5 Answer ||| C Solution ||| Given that

2

2

m =100kg,g=10m/sec ,E=100GPa

H =10mm,L=1m=100mm,

A =100mm

From the given figure, we can say that this is case of Impact loading,

We know that, stress due to Impact load is

30. One kg of an ideal gas (gas constant, R = 400 J/kg.K; specific heat at constant volume,

1000 / . )vc J kg K

at 1 bar, and 300 K is contained in a sealed rigid cylinder. During an adiabatic process, 100kJ of work is done on the system by a stirrer. The increase in entropy of the

system is _________ J/K. A. 287.6821 B. 274.1274 C. 295.4266 D. 300.3154 Answer ||| A

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7 | P a g e

Solution ||| Given that 1 ,m kg

400 / ,

1000 /v

R Kj kgK

C J kgK

1 11 , 300P bar T K

Since the gas is contained in a sealed rigid cylinder, and

given that adiabatic process is done to the system, means no heat is transferred from/to the system, Q = 0 and we know from first law of thermo dynamics,

We know that the first law of thermodynamics can be written as

31. For an inline slider-crank mechanism, the lengths of the crank and connecting rod are 3m and 4m, respectively. At the instant when the connecting rod is perpendicular to the crank, if the velocity of the slider is 1m/s, the magnitude of angular velocity (upto 3 decimal

points accuracy) of the crank is _________ radian/s. A. 0.222 B. 0.267 C. 0.298 D. 0.316 Answer ||| B

Solution ||| Given that velocity of slider

1 / secBV m

Length of crank (OA) = 3m Length of connecting rod (AB) = 4m

From the configuration diagram

sin5

53.130

A

The velocity diagram for the above configuration diagram is

32. In an epicyclic gear train, shown in the figure, the

outer ring gear is fixed, while the sun gear rotates counterclockwise at 100rpm. Let the number of teeth on the sun, planet and outer gears to be 50, 25, and 100, respectively. The ratio of magnitudes of angular velocity of the planet gear to the angular velocity of the carrier arm is _________.

A. 3 B. 4

C. 5 D. 6 Answer ||| A

Solution ||| 50ST

25

100

P

R

T

T

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8 | P a g e

100sN x y ...(1)

500

100RN y x

0.5y x ...(2)

0.5 100

10066.66

1.5

33.34

5033.34 66.66 99.99

25P

x x

x rpm

y rpm

N rpm

99.993( )

33.32

P

arm

Napprox

N

33. Moist air is treated as an ideal gas mixture of water vapor and dry air (molecular weight of air = 28.84 and molecular weight of water = 18). At a location, the total pressure is 100 kPa, the temperature is 30°C and the

relative humidity is 55%. Given that the saturation pressure of water at 30°C is 4246 Pa, the mass of water

vapor per kg of dry air is _____________ grams. A. 13.7 B. 14.8 C. 15.4 D. 16.9

Answer ||| B

Solution ||| 28.84aM

34. Following data refers to the jobs (P, Q, R, S) which have arrived at a machine for scheduling. The shortest possible average flow time is ___________ days.

A. 21

B. 25 C. 29 D. 31 Answer ||| D Solution ||| For shortest avg. flow time SPT rule is used

Min Avg. Flow time9 21 36 58

314

days

35. Two models, P and Q, of a product earn profits of Rs. 100 and Rs. 80 per piece, respectively. Production times for P and Q are 5 hours and 3 hours, respectively, while the total production time available is 150 hours. For a total batch size of 40, to maximize profit, the number of

units of P to be produced is ____________. A. 12 B. 15 C. 18 D. 20 Answer ||| B

Solution ||| Let 1x No. of units of P

2x No. of units of Q

.  max1 2100 80z x x

1 2

1 2

5 3 150

40

x x

x x

(0,40)

(15,225)

.3200

.3500 max.

Z Rs

Z Rs profit

So, for maximum profit, No. of units of P produced is 15 units. 36. Circular arc on a part profile is being machined on a vertical CNC milling machine. CNC part program using

metric units with absolute dimensions is listed below: ------------------------------ N60 G01 X 30 Y 55 Z – 5 F 50 N70 G02 X 50 Y 35 R 20 N80 G01 Z 5 -------------------------------- The coordinates of the centre of the circular arc are :

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9 | P a g e

A. (30, 55) B. (50, 55) C. (50, 35) D. (30, 35) Answer ||| D

Solution |||

Centre of circular arc is (30, 35) 37. Two black surfaces, AB and BC, of lengths 5m and 6m, respectively, are oriented as shown. Both surfaces

extend infinitely into the third dimension. Given that view factor F12=0.5, T1=800K, T2=600K, Tsurrounding=300K

and Stefan Boltzmann constant

8 2 45.67 10 / ,W m K the heat transfer rate from

Surface 2 to the surrounding environment is

____________ kW.

A. 12.85 B. 13.77

C. 15.23

D. 17.33 Answer ||| B Solution ||| Given that two black surfaces ‘AB’ and ‘BC’

Length of AB = 5m, BC = 6 m And temperature of

8 2 4

21 2

12

11

2 23

1

22

12 2 21

=5.67 10 W/m K

F =0.5

W.K.T.F =F =0,         

1

sincethey are flat surfaces

F F F

AF A F

216 0.5 5 F

(Assume unit width for surfaces)

21

23 23

30.6

5

0.6 0 1 1 0.6 0.4

F

F F

Using resistance concept we can draw as follows Since surfaces are black and area of surrounding is large

we can write

1 2 2 3 3

4 4

2 3 2 323

2 232 23

8 4 4

, ,

( )

11

5.67 10 600 300 5 0.4

13.778 /

bl b b

b b

E J B J E J

E E T TQ

A FA F

kW metre

38. Consider the matrix

1 10

2 2

0 1 0

1 10

2 2

P

Which one of the following statements about P is INCORRECT? A. Determinant of P is equal to 1. B. P is orthogonal. C. Inverse of P is equal to its transpose.

D. All Eigen values of P are real numbers Answer ||| D

Solution |||

1 10

2 2

0 1 0

1 10

2 2

P

1 1 1 10 0

2 2 2 2

1 11

2 2

P

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10 | P a g e

1 1 1 10 0

2 2 2 2

. 0 1 0 0 1 0

1 1 1 10 0

2 2 2 2

TP P

1 0 0

0 1 0

0 0 1

P is an orthogonal matrix

(A) Is correct Inverse of P is its transpose only

(B) and (C) both are correct

(D) is incorrect

39. The Pressure ratio across a gas turbine (for air,

specific heat at constant pressure, 1040 / .pC J kg K

and ratio of specific heats, 1.4) is 10. If the inlet

temperature to the turbine is 1200K and the isentropic

efficiency is 0.9, the gas temperature at turbine exit is ______ K. A. 666.22 B. 679.28 C. 675.10 D. 680.11 Answer ||| B

Solution |||

2 1 3

1040 / . , 1.4

/ 10, 1200

0.9

p

is

C J kg K r

P P T K

Isentropic Expansion,

1

0.4/1.43 3

4 4 4

4

1

3 4

3 4

1

4 3 3 4

4

120010

621.5

,

1200 09(1200 621.5)

679.38

r

r

iso

iso

P T

P T T

T K

T T

T T

So T T T T

T K

40. An initially stress-free massless elastic beam of length L and circular cross-section with diameter d (d <<

L) is held fixed between two walls as shown. The beam material has Young‟s modulus E and coefficient of thermal expansion

If the beam is slowly and uniformly heated, the temperature rise required to cause the beam to buckle is proportional to

A. d B. 2d

C. 3d D.

4d

Answer ||| B

Solution |||

41. For the vector the value of is ____________

the value of

____________ A. 0 B. 1 C. 2 D. 3 Answer ||| A

42. A 10 mm deep cylindrical cup with diameter of 15mm is drawn from a circular blank. Neglecting the variation in the sheet thickness, the diameter (upto 2 decimal points accuracy) of the blank is _________ mm. A. 27.12 B. 28.72

C. 29.49 D. 33.41 Answer ||| B

Solution ||| 2 4D d dh

215 4 10 15

28.72mm

43. A machine element has an ultimate strength

2   600 /u of N mm , and endurance limit of

2250 /N mm . The fatigue curve for the element on log-

log plot is shown below. If the element is to be designed for a finite of 10000 cycles, the maximum amplitude of a completely reversed operating stress is _________

2/N mm .

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A. 350 B. 365.23 C. 386.19 D. 395

Answer ||| C Solution |||

600u MPa

250

10000

en MPa

N cycle

log 0.8 log 250 log 0.8 log

3 6 3 4

u u

log 480 log 250 log 480 log

3 3 4

3log 480 log 480 log 250log

3

2log 480 log 250

3

max 386.19MPa

44. A sprue in a sand mould has a top diameter of 20mm and height of 200mm. The velocity of the molten metal at the entry of the sprue is 0.5m/s. Assume acceleration due to gravity as 9.8 m/s2 and neglect all losses. If the

mould is well ventilated, the velocity (upto 3 decimal points accuracy) of the molten metal at the bottom of the sprue is ________ m/s.

A. 1.707 B. 2.042 C. 2.358 D. 2.443 Answer ||| B Solution ||| Apply Bernoulli‟s between (1) and (2)

2 2

1 1 2 21 2

22

2

2

2 2

0.50.2

2 2

2.042 /

P V P Vz z

g g

V

g g

V m s

45. Air contains 79% N2 and 21% O2 on a molar basis. Methane (CH4) is burned with 50% excess air than required stoichiometrically. Assuming complete combustion of methane, the molar percentage of N2 in the products is ________________ A. 70 B. 73.8

C. 75 D. 79.8 Answer ||| B Solution ||| Stoichiometric reaction

4 2 2 2 2 2

79 792. 2 2

21 21CH O N H O CO N

50% excess air

4 2 2 2 2 2 2

79 793. 2 3

21 21CH O N H O CO N O

2

3 79

21% 100 73.83%79

2 1 1 321

N

46. P(0,3), Q(0.5, 4), and R (1,5) are three points on the curve defined by f(x). Numerical integration is carried out

using both Trapezoidal rule and Simpson‟s rule within limits x = 0 and x =1 for the curve. The difference between the two results will be.

A. 0 B. 0.25 C. 0.5 D. 1 Answer ||| A

Solution ||| Let

Trapezoidial rule

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12 | P a g e

1

0

0.53 5 2 4

2

0.516

2

4

f x dx

Simpsons rule

1

0

0.53 5 0 4 4

3

0.524

3

4

f x dx

Difference =0

47. Heat is generated uniformly in a long solid cylindrical

rod (diameter = 10mm) at the rate of7 34 10 /W m .

The thermal conductivity of the rod material is 25W/m.K. Under steady state conditions, the temperature difference between the centre and the surface of the rod is _________ °C. A. 7 B. 8

C. 9 D. 10 Answer ||| D Solution ||| Given that, heat is generated uniformly

7 3. ., 4 10 /i e g W m Diameter at the rod (d) = 10 mm

Thermal conductivity of the rod (K) = 25 W/mK

W.K.T. for steady state, with internal heat generation, the conduction equation will be,

1. 0

. 0

d dT gr

r dr dr k

d dT grr

dr dr K

After Integration once

2

1

1

.

12

dT grr Cdr K

cdT gr

dr K r

After second Integration

2

1 2 24

grT r C n r C

K

Substituting boundary condition of

0    0    1at rdT

drineq

That gives 1 0C

2

2 ,4

grT r C

k

substitute at 0, or T r T

2 2

2

0

4

o o

o

T C C T

grT r T

K

Substitute 0

105 0.005

2r r mm m and sT r T

The above equation will become 2

0

7 2

0

4

4 10 0.00510

4 25

s

s

grT T

K

T T C

48. Two disks A and B with identical mass (m) and radius (R) are initially at rest. They roll down from the top of identical inclined planes without slipping. Disk A has all of its mass concentrated at the rim, while Disk B has its

mass uniformly distributed. At the bottom of the plane, the ratio of velocity of the center of disk A to the velocity of the center of disk B is.

A. 3

4 B.

3

4

C. 1 D. 2

Answer ||| A

Solution ||| 2

AI MR

2

2B

MRI

2 2 2 2

22 2 2 2 2

. . . . . .

1 1 1 1

2 2 2 2

1 1 1 1

2 2 2 2 2

T R T RA B

A A B B

A A B B

P E K E K E K E K E

MV I MV I

MRMV MR MV

22 2 2

2 2

2

3 32

2 4

BA A B

AA B

B

VV V V

VV V

V

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13 | P a g e

49. A block of length 200mm is machined by a slab milling cutter 34mm in diameter. The depth of cut and table feed are set at 2mm and 18mm/minute,

respectively. Considering the approach and the over

travel of the cutter to be same, the minimum estimated machining time per pass is _____________ minutes. A. 6 B. 10 C. 12 D. 16 Answer ||| C

Solution |||

Milling Time

22 Dd d L

f

22 34 2 2 200

18

12

Where, D= Dia of cutter (mm) ,

d=depth of cut (mm) L= length F= feed (mm /min) 50. A horizontal bar, fixed at one end (x = 0), has a

length of 1 m, and cross-sectional area of2100mm . Its

elastic modulus varies along its length as given by

100 xE x e GPa , Where x is the length coordinate

(in m) along the axis of the bar. An axial tensile load of

10 kN is applied at the free end (x=1). The axial displacement of the free end is _______ mm. A. 1.47

B. 1.53 C. 1.66 D. 1.71 Answer ||| D

Solution ||| Given that

3 2

95

6

10 10 10 , 100

100 10100 10

10

xx x

P kN N A mm

eE x e GPa e

Change in the length of small strip

x

P dx

AE

Total change in the length of the bar 0

L

x

Pdx

AE

5

0 0

5 5

0 0

1

5

3

5

100 10

10 10

110

10 102.7183 1 1000

100 10

1.7183

L L

x x

L l

x x

P dx P dx

A e A e

P Pe dx e dx

A A

Pe

A

mm

51. Consider steady flow of an incompressible fluid through two long and straight pipes of diameters d1 and d2 arranged in series. Both pipes are of equal length and

the flow is turbulent in both pipes. The friction factor for

turbulent flow though pipes is of the form Ren

f K

,

where K and n are known positive constants and Re is the Reynolds number. Neglecting minor losses, the ratio of the frictional pressure drop in pipe 1 to that in pipe 2,

1

2

P

P

, is given by

A.

5

2

1

n

d

d

B.

5

2

1

d

d

C.

3

2

1

n

d

d

D.

5

2

1

n

d

d

Answer ||| A Solution |||

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14 | P a g e

5

1 1 2

2 2 1

5

1 2

2 1

1     1

n

n

n

P d d

P d d

P d

P

Re Fromd

d

52. The velocity profile inside the boundary layer for flow

over a flat plate is given as sin2

u y

U

, whereU

is the free stream velocity and is the local boundary

layer thickness. If * is the local displacement thickness,

the value of

*

is

A. 2

B.

21

C. 2

1

D. 0

Answer ||| B

Solution ||| sin2

u y

U

displacement thickness

*

01 / 1 sin

2

yU U dy dy

*

*

*

*

cos / 2

/ 2

2cos / 2 cos 0

2

/ 1 2 /

y

53. For a steady flow, the velocity field is

The magnitude of the acceleration of a particle at (1, -1) is

A. 2 B. 1

C. 2 5 D. 0

Answer ||| C

Solution |||

2 3

2

U x y

V xy

2

3

3

3 2 2 3

2 6 6

2

x

U Ua U V

x y

x y x xy

x xy xy

x

2

2 2 2

2 2

3 2 2 2

2 6 4

2 6

y

V Va U V

x y

x y x xy x

x y y x y

x y y

But x=1, y=1

2xa

2 2

2 1 1 6 1

6 2

4

ya

2 2

4 16

20

2 5

x ya a a

54. Two cutting tools with tool life equations given below

are being compared:

Tool 1: 0.1 150VT

Tool 2: 0.3 300VT

Where V is cutting speed in m/minute and T is tool life in minutes. The breakeven cutting speed beyond which Tool 2 will have a higher tool life is ________ m/minute. A. 106

B. 110 C. 113 D. 117 Answer ||| A Solution ||| At Breakeven point

1 2

1 0.1 1 0.3150 300

106.121 / min

T T

V V

V m

55. A rectangular region in a solid is in a state of plane

strain. The (x,y) coordinates of the corners of the under deformed rectangle are given by P(0,0), Q (4,0), S (0,3). The rectangle is subjected to uniform strains,

0.001, 0.002, 0.003.xx xy xy The deformed

length of the elongated diagonal, up to three decimal

places, is _________ units.

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15 | P a g e

A. 4.50 B. 4.80 C. 5.014

D. 6.3489

Answer ||| C Solution ||| Given that

0.001, 0.002, 0.003.xx xy xy Length of the

diagonal 2 24 3 5PR m

To find the diagonal (PR) strain, the direction of the plane

angle from the +ve x-axis will from ‘R’ towards ‘P’

?

Where

1180 tan 3 / 4

216.87

216.87cos 2 sin 2

2 2 2

xy yy xx yy xyr

4 3

3

0.001 0.002 0.001 0.002cos 2 216.87

2 2

0.003sin 2 216.87

2

0.0015 1.4 10 1.44 10

2.8 10

Elongation of the diagonal3

216.87 5 2.8 10 5 0.014

Defined length of

diagonal 5 0.014 5.014

56. A right – angled cone (with base radius 5cm and height 12cm), as shown in the figure below, is rolled on the ground keeping the point P fixed until the point Q (at the base of the cone, as shown) touches the ground

again.

By what angle (in radians) about P does the cone travel?

A. 5

12

B.

5

24

C. 24

5

D.

10

13

Answer ||| D

Solution ||| 2 25 12 13L cm

Circumference of base circle = length of arc QR

2 r R (R Slant height of the Cone 13 cm)

2 5 13

10

13

57. In a company with 100 employees, 45 earn Rs. 20,000 per month, 25 earn Rs. 30,000, 20 earn Rs. 40,000,8 earn Rs. 60,000, and 2 earn Rs. 150,000. The median of the salaries is A. Rs. 20,000 B. Rs.30,000

C. Rs. 32,300 D. Rs. 40,000 Answer ||| B Solution ||| All the values put either in ascending or descending order first. Now number of observations equal

to 100 [even]

The median of these values = Avg of two middle most

observations.

50 51

2

30,000 30,000

2

30,000

th stobservation observation

58. As the two speakers became increasingly agitated, the debate became __________. A. lukewarm B. poetic

C. forgiving D. heated

Answer ||| D Solution ||| Best answer will be heated as agitated defines the debate shifting to hard talk between speakers 59. P,Q, and R talk about S‟s car collection. P states that

S has at least 3 cars. Q believes that S has less than 3 cars. R indicates that to his knowledge, S has at least one Car. Only one of P, Q and R is right the number cars owned by S is. A. 0 B. 1 C. 3

D. Cannot be determined Answer ||| A

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Solution ||| P States that S has atleast 3 cars, i.e., 3

Q believes that S has less than 3 cars, i.e.,< 3

R indicates that S has atleast one car 1

P‟s and Q‟s statements are exactly opposite in nature and R‟s statement is proportional to P‟s statement. From the given data, only one person statement is right

as it mean that two persons statements are wrong, i.e., P and R wrong when S has zero cars. 60. He was one of my best __________ and I felt his loss _________. A. friend, keenly

B. friends, keen C. friend, keener D. friends, keenly Answer ||| D Solution ||| Best answer is friends, keenly

61. Two very famous sportsmen Mark and Steve

happened to be brothers, and played for country K. Mark teased James, an opponent from country E, “There is no way you are good enough to play for your country.‟‟ James replied, “Maybe not, but at least I am the best player in my own family.” Which one of the following can be inferred from this conversation? A. Mark was known to play better than James

B. Steve was known to play better than Mark C. James and Steve were good friends D. James played better than Steve Answer ||| B Solution ||| James reply was return to Mark’s tease. Mark although played for his country but still he was not better

player than his brother i.e Steve

62. “Here, throughout the early 1820s, Stuart continued to fight his losing battle to allow his sepoys to wear their caste-marks and their own choice of facial hair on parade, being again reprimanded by the commander-in-chief. His retort that „A stronger instance than this of

European prejudice with relation to this country has never come under my observations‟ had no effect on his superiors.” According to this paragraph, which of the statements below is most accurate? A. Stuart‟s commander – in chief was moved by this demonstration of his prejudice.

B. The Europeans were accommodating of the sepoys‟ desire to wear their caste – marks. C. Stuart‟s losing battle‟ refers to his inability to succeed in enabling sepoys to wear caste-marks.

D. The commander– in – Chief was exempt from the European preiudice that dictated how the sepoys were to

dress. Answer ||| C Solution ||| Best answer is C 63. The growth of bacteria (lactobacillus) in milk leads to curd formation. A minimum bacterial population density of 0.8(in suitable units) is needed to form curd. In the

graph below, the population density of lactobacillus in 1 litre of milk is plotted as a function of time, at two different temperatures, 25ºC and 37°C. .

Consider the following statements based on the data shown above: (i) The growth in bacterial population stops earlier at

37°C as compared to 25°C (ii) The time taken for curd formation at 25°C is twice the time taken at 37°C Which one of the following options is

correct? A. Only i B. only ii C. Both i and ii D. Neither i nor ii Answer ||| A Solution ||| From the graph, Statement (i) is correct,

The time taken for curd formation @25o C= 120 min, the time taken for curd formation @ 37o C= 80 min, hence (ii) is incorrect. 64. Let S1 be the plane figure consisting of the points

(x,y) given by the inequalities 1 2x and 2 3.y

Let S2 be the plane figure given by the inequalities

2, 1,x y y and 3x Let S be the union of S1 and

S2. The area of S is. A. 26 B. 28 C. 32 D. 34 Answer ||| C Solution ||| Answer is 32

65. What is the sum of the missing digits in the subtraction problem below? 5 _ _ _ _

48 _ 89

1111

A. 8

B. 10 C. 11 D. Cannot be determined Answer ||| D Solution ||| Insufficient data

***