Mechanical Engineering - Online Test
Q1. A room contains 35 kg of dry air and 0.5 kg of water vapor. The total pressure and temperature of
air in the room are 100 kPa and 25℃ respectively. Given that the saturation pressure for water at
25℃ is 3.17 kPa, the relative humidity of the air in the room is
Answer : Option D
Explaination / Solution:
No Explaination.
Q2. For |x| << 1, coth (x) can be approximated as
Answer : Option C
Explaination / Solution:
Q3. Friction at the tool-chip interface can be reduced by
Answer : Option D
Explaination / Solution:
No Explaination.
Q4. The piston rod of diameter 20 mm and length 700 mm in a hydraulic cylinder is
subjected to a compressive force of 10 kN due to the internal pressure. The end
conditions for the rod may be assumed as guided at the piston end and hinged
at the other end. The Young’s modulus is 200 GPa. The factor of safety for the
piston rod is
Answer : Option C
Explaination / Solution:
Elusive: Difficult to answer.
Q5. An incompressible fluid flows over a flat plate with zero pressure gradients. The boundary layer
thickness is 1 mm at a location where the Reynolds number is 1000. If the velocity of the fluid
alone is increased by a factor of 4, then the boundary layer thickness at the same location, in mm
will be
Answer : Option C
Explaination / Solution:
No Explaination.
Q6. 
Answer : Option A
Explaination / Solution:
Q7. Two streams of liquid metal, which are not hot enough to fuse properly result into a casting defect
known as
Answer : Option A
Explaination / Solution:
No Explaination.
Q8. A thin walled spherical shell is subjected to an internal pressure. If the radius of the shell is
increased by 1% and the thickness is reduced by 1%, with the internal pressure remaining the
same, the percentage change in the circumferential (hoop) stress is
Answer : Option D
Explaination / Solution:
Q9. A solid steel cube constrained on all six faces is heated so that the temperature rises uniformly by
∆T. If the thermal coefficient of the material is α. Young’s modulus is E and the Poissons’s ratio
is υ, the thermal stress developed in the cube due to heating is
Answer : Option A
Explaination / Solution:
No Explaination.
Q10. Which one of following functions is strictly bounded?
Answer : Option D
Explaination / Solution:
