1 In PERT analysis a critical activity has
A) maximum Float
B) zero Float
C) maximum Cost
D) minimum Cost
Answer : (B)

2 Environment friendly refrigerant R134a is used in the new generation domestic refrigerators. Its chemical formula is
A) CH C1 F2
B) C2 C13 F3
C) C2 C12 F4
D) C2 H2 F4
Answer : (D)

3 A solid cylinder (surface 2) is located at the centre of a hollow sphere (surface 1). The diameter of the sphere is 1m, while the cylinder has a diameter and length of 0.5 m each. The radiation configuration factor F11 is
A) 0.375
B) 0.625
C) 0.75
D) 1
Answer : (C)

4 For a fluid flow through a divergent pipe of length L having inlet and outlet radii of R1 and R2 respectively and a constant flow rate of Q, assuming the velocity to be axial and uniform at any cross-section, the acceleration at the exit is
A) 2Q(R1 - R2) p LR23
B) 2Q2 (R1 - R2) p LR23
C) 2Q2 (R1 - R2) p2LR25
D) 2Q2 (R2 - R1) p2LR25
Answer : (C)

5 An incompressible fluid (kinematic viscosity, 7.4 x 10-7 m2/s, specific gravity, 0.88) is held between two parallel plates. If the top plate is moved with a velocity of 0.5 m/s while the bottom one is held stationary, the fluid attains a linear velocity profile in the gap of 0.5 mm between these plates; the shear stress in Pascals on the surface of top plate is
A) 0.651 x 10-3
B) 0.651
C) 6.51
D) 0.651 x 103
Answer : (B)

6 The tool of an NC machine has to move along a circular arc from (5,5) to (10,10) while performing an operation. The centre of the arc is at (10,5). Which one of the following NC tool path commands performs the above mentioned operation?
A) N010 G02 X10 Y10 X5 Y5 R5
B) N010 G03 X10 Y10 X5 Y5 R5
C) N010 G01 X5 Y5 X10 Y10 R5
D) N010 G02 X5 Y5 X10 Y10 R5
Answer : (D)

7 During a Morse test on a 4 cylinder engine, the following measurements of brake power were taken at constant speed.
All cylinders firing 3037 kW
Number 1 cylinder not firing 2102 kW
Number 2 cylinder not firing 2102 kW
Number 3 cylinder not firing 2100 kW
Number 4 cylinder not firing 2098 kW
The mechanical efficiency of the engine is
A) 91.53%
B) 85.07%
C) 81.07%
D) 61.22%
Answer : (C)

8 In terms of theoretical stress concentration factor (Kt) and fatigue stress concentration factor (Kf ), the notch sensitivity ‘q’ is expressed as
A) (Kf -1) (Kt -1)
B) (Kf -1) (Kt +1)
C) (Kt -1) (Kf -1)
D) (Kf +1) (Kt +1)
Answer : (A)