ISRO Past Year Paper (Mechanical) - 2018 - ISRO, GATE & IES/ESE Mechanical Previous Year Solved Papers - Mechanical Engineering

 Page 1


ISRO Scientist or Engineer Mechanical 2018
               
              
               
 
  
.
Page 2


ISRO Scientist or Engineer Mechanical 2018
               
              
               
 
  
.
Mechanical
Instructions
For the following questions answer them individually
Question 1
An expansion process as per law PV = constant is known as
A    parabolic expansion
B    hyperbolic expansion
C    isentropic expansion
D    free expansion
Answer: B
Question 2
Speed of an aeroplane is measured by
A    pitot tube
B    hot wire anemometer
C    venturimeter
D    rotameter
Answer: A
Question 3
Euler's dimensionless number relates the following
A    inertial force and gravity
B    viscous force and inertial force
C    pressure force and inertial force
D    viscous force and pressure force
Answer: C
Question 4
A simple compressible substance inside a cylinder undergoes a change of state quasistatically, isothermally and at constant pressure
of 1.5 MPa. If the enthalpy change for the system is 4000 kJ at , what is the corresponding change in its entropy?
A    9.45 kJ/K
B    26.67 kJ/K
C    14.17 kJ/K
D    0
Answer: A
1 5 0 C
°
  
.
Page 3


ISRO Scientist or Engineer Mechanical 2018
               
              
               
 
  
.
Mechanical
Instructions
For the following questions answer them individually
Question 1
An expansion process as per law PV = constant is known as
A    parabolic expansion
B    hyperbolic expansion
C    isentropic expansion
D    free expansion
Answer: B
Question 2
Speed of an aeroplane is measured by
A    pitot tube
B    hot wire anemometer
C    venturimeter
D    rotameter
Answer: A
Question 3
Euler's dimensionless number relates the following
A    inertial force and gravity
B    viscous force and inertial force
C    pressure force and inertial force
D    viscous force and pressure force
Answer: C
Question 4
A simple compressible substance inside a cylinder undergoes a change of state quasistatically, isothermally and at constant pressure
of 1.5 MPa. If the enthalpy change for the system is 4000 kJ at , what is the corresponding change in its entropy?
A    9.45 kJ/K
B    26.67 kJ/K
C    14.17 kJ/K
D    0
Answer: A
1 5 0 C
°
  
.
Question 5
The velocity of sound in a gaseous medium at a temperature of 400 K is 400 m/s. If the temperature of the medium is increased to
600 K, the velocity of sound will be nearly,
A    400 m/s
B    490 m/s
C    600 m/s
D    None of these
Answer: B
Question 6
Stress strain relation of the Newtonian fluid is
A    parabolic
B    linear
C    hyperbolic
D    inverse type
Answer: B
Question 7
Speed of sound in water is equal to (K-bulk modulus, -density)
A    
B    
C    
D    
Answer: A
Question 8
If the stream function of a two dimensional flow is . then the velocity at a point (3, 4)is
A    25 m/s
B    20 m/s
C    7 m/s
D    5 m/s
Answer: A
Question 9
A glass tube of 8 mm diameter is immersed in water. Surface tension of water is 0.0075 kg/m and rise of water in the tube due to
capillary effect is
?
?
K
K ?
K
?
?
K
? = 5 x y
  
.
Page 4


ISRO Scientist or Engineer Mechanical 2018
               
              
               
 
  
.
Mechanical
Instructions
For the following questions answer them individually
Question 1
An expansion process as per law PV = constant is known as
A    parabolic expansion
B    hyperbolic expansion
C    isentropic expansion
D    free expansion
Answer: B
Question 2
Speed of an aeroplane is measured by
A    pitot tube
B    hot wire anemometer
C    venturimeter
D    rotameter
Answer: A
Question 3
Euler's dimensionless number relates the following
A    inertial force and gravity
B    viscous force and inertial force
C    pressure force and inertial force
D    viscous force and pressure force
Answer: C
Question 4
A simple compressible substance inside a cylinder undergoes a change of state quasistatically, isothermally and at constant pressure
of 1.5 MPa. If the enthalpy change for the system is 4000 kJ at , what is the corresponding change in its entropy?
A    9.45 kJ/K
B    26.67 kJ/K
C    14.17 kJ/K
D    0
Answer: A
1 5 0 C
°
  
.
Question 5
The velocity of sound in a gaseous medium at a temperature of 400 K is 400 m/s. If the temperature of the medium is increased to
600 K, the velocity of sound will be nearly,
A    400 m/s
B    490 m/s
C    600 m/s
D    None of these
Answer: B
Question 6
Stress strain relation of the Newtonian fluid is
A    parabolic
B    linear
C    hyperbolic
D    inverse type
Answer: B
Question 7
Speed of sound in water is equal to (K-bulk modulus, -density)
A    
B    
C    
D    
Answer: A
Question 8
If the stream function of a two dimensional flow is . then the velocity at a point (3, 4)is
A    25 m/s
B    20 m/s
C    7 m/s
D    5 m/s
Answer: A
Question 9
A glass tube of 8 mm diameter is immersed in water. Surface tension of water is 0.0075 kg/m and rise of water in the tube due to
capillary effect is
?
?
K
K ?
K
?
?
K
? = 5 x y
  
.
A    7.5 mm
B    3.75 mm
C    11.25 mm
D    none of these
Answer: B
Question 10
An impulse turbine produces 125 hp under a head of 25 meter. By what percentage should the speed be increased for a head of 100
meter.
A    25%
B    50%
C    75%
D    100%
Answer: D
Question 11
The specific speed of a centrifugal pump, delivering 1000litres of water per second against a head of 16 meter at 800 rom
A    50 rpm
B    100 rpm
C    150 rpm
D    200 rpm
Answer: B
Question 12
A pipe of 0.1 m suddenly changes to 0.5 m area. The quantity of water flowing in the pipe is 0.5 m /s. Head loss due to sudden
enlargement is nearly
A    0.025 m
B    0.05 m
C    0.8 m
D    1.2 m
Answer: C
Question 13
Efficiency of a centrifugal pump is maximum when the blades are
A    straight
B    forward curved
2 2 3
  
.
Page 5


ISRO Scientist or Engineer Mechanical 2018
               
              
               
 
  
.
Mechanical
Instructions
For the following questions answer them individually
Question 1
An expansion process as per law PV = constant is known as
A    parabolic expansion
B    hyperbolic expansion
C    isentropic expansion
D    free expansion
Answer: B
Question 2
Speed of an aeroplane is measured by
A    pitot tube
B    hot wire anemometer
C    venturimeter
D    rotameter
Answer: A
Question 3
Euler's dimensionless number relates the following
A    inertial force and gravity
B    viscous force and inertial force
C    pressure force and inertial force
D    viscous force and pressure force
Answer: C
Question 4
A simple compressible substance inside a cylinder undergoes a change of state quasistatically, isothermally and at constant pressure
of 1.5 MPa. If the enthalpy change for the system is 4000 kJ at , what is the corresponding change in its entropy?
A    9.45 kJ/K
B    26.67 kJ/K
C    14.17 kJ/K
D    0
Answer: A
1 5 0 C
°
  
.
Question 5
The velocity of sound in a gaseous medium at a temperature of 400 K is 400 m/s. If the temperature of the medium is increased to
600 K, the velocity of sound will be nearly,
A    400 m/s
B    490 m/s
C    600 m/s
D    None of these
Answer: B
Question 6
Stress strain relation of the Newtonian fluid is
A    parabolic
B    linear
C    hyperbolic
D    inverse type
Answer: B
Question 7
Speed of sound in water is equal to (K-bulk modulus, -density)
A    
B    
C    
D    
Answer: A
Question 8
If the stream function of a two dimensional flow is . then the velocity at a point (3, 4)is
A    25 m/s
B    20 m/s
C    7 m/s
D    5 m/s
Answer: A
Question 9
A glass tube of 8 mm diameter is immersed in water. Surface tension of water is 0.0075 kg/m and rise of water in the tube due to
capillary effect is
?
?
K
K ?
K
?
?
K
? = 5 x y
  
.
A    7.5 mm
B    3.75 mm
C    11.25 mm
D    none of these
Answer: B
Question 10
An impulse turbine produces 125 hp under a head of 25 meter. By what percentage should the speed be increased for a head of 100
meter.
A    25%
B    50%
C    75%
D    100%
Answer: D
Question 11
The specific speed of a centrifugal pump, delivering 1000litres of water per second against a head of 16 meter at 800 rom
A    50 rpm
B    100 rpm
C    150 rpm
D    200 rpm
Answer: B
Question 12
A pipe of 0.1 m suddenly changes to 0.5 m area. The quantity of water flowing in the pipe is 0.5 m /s. Head loss due to sudden
enlargement is nearly
A    0.025 m
B    0.05 m
C    0.8 m
D    1.2 m
Answer: C
Question 13
Efficiency of a centrifugal pump is maximum when the blades are
A    straight
B    forward curved
2 2 3
  
.
C    
backward curved
D    forward and backward curved
Answer: C
Question 14
The critical radius of insulation for a spherical shell is
A    
B    
C    
D    
Answer: B
Question 15
If the temperature of a solid surface changes from  to , then its emissive power changes in the ratio of nearly
A    81
B    9
C    1.49
D    1.94
Answer: D
Question 16
The heat removal rate from a refrigerated space is 7.2 kW and the power input to the compressor is 1.8 kW. The coefficient of
performance (COP) of the refrigerator is
A    4
B    5
C    1.25
D    0.25
Answer: A
Question 17
For a fluid having Prandtl number equal to unity, the relation between hydrodynamic boundary layer thickness ( ) and thermal
boundary layer thickness ( )
A    
B    
C    
h e a t t r a n s f e r c o e f f i c i e n t a t t h e o u t e r s u r f a c e
t h e r m a l c o n d u c t i v i t y o f i n s u l a t i n g m a t e r i a l
h e a t t r a n s f e r c o e f f i c i e n t a t t h e o u t e r s u r f a c e
2 × t h e r m a l c o n d u c t i v i t y o f i n s u l a t i n g m a t e r i a l
2 × h e a t t r a n s f e r c o e f f i c i e n t a t t h e o u t e r s u r f a c e
t h e r m a l c o n d u c t i v i t y o f i n s u l a t i n g m a t e r i a l
t h e r m a l c o n d u c t i v i t y o f i n s u l a t i n g m a t e r i a l
h e a t t r a n s f e r c o e f f i c i e n t a t t h e o u t e r s u r f a c e
2 7 i r c C
c
8 1 i r c C
c
d 1
d 2
d > 1 d 2
d < 1 d 2
d = 1 d 2
d
  
.