Mechanical Engineering - Online Test
Q1. Let A be a 4 × 3 real matrix with rank 2. Which one of the following statement is TRUE?
Answer : Option B
Explaination / Solution:
Q2. A steel plate, connected to a fixed channel using three identical bolts A, B and C, carries a
load of 6kN as shown in the figure. Considering the effect of direct load and moment, the
magnitude of resultant shear force (in kN) on bolt C is.
Answer : Option C
Explaination / Solution:
Primary shear = 6/3 = 2kN
Secondaryshear 1500 kN - mm
Resultantshear at 'C' = 2 + 15 = 17kN
Resultant shear = 15 + 2 = 17 kN
Q3. During the turning of a 20mm-diameter steel bar at a spindle speed of 400 rpm, a tool life of
20 minute is obtained. When the same bar is turned at 200 rpm, the tool life becomes 60
minute. Assume that Taylor's tool life equation is valid. When the bar is turned at 300 rpm, the
tool life (in minute) is approximately.
Answer : Option B
Explaination / Solution:
Taylors Tool life equation,
Q4. In a linear arc welding process, the heat input per unit length is inversely proportional to
Answer : Option D
Explaination / Solution:
No Explaination.
Q5. Shaquille O’ Neal is a 60% career free throw shooter, meaning that he successfully makes 60 free throws out of 100 attempts on average. What is the probability that he will successfully make exactly 6 free throws in 10 attempts?
Answer : Option A
Explaination / Solution:
Q6. A rod of length 20mm is stretched to make a rod of length 40 mm. Subsequently, it is
compressed to make a rod of final length 10mm. Consider the longitudinal tensile strain as
positive and compressive strain as negative. The total true longitudinal strain in the rod is
Answer : Option B
Explaination / Solution:
Q7. The instantaneous stream-wise velocity of a turbulent flow is
given as follows:
The time-average of the fluctuating velocity u’(x, y, z, t) is
Answer : Option C
Explaination / Solution:
No Explaination.
Q8. The solidification time of a casting is proportional to (V/A)2, where V is the volume of the
casting and A is the total casting surface area losing heat. Two cubes of same material and
size are cast using sand casting process. The top face of one of the cubes is completely
insulated. The ratio of the solidification time for the cube with top face insulated to that of the
other cube is
Answer : Option B
Explaination / Solution:
Q9. A 3 × 3 matrix P is such that, P3 = P. Then the eigenvalues of P are
Answer : Option D
Explaination / Solution:
Q10. The principal stresses at a point in a critical section of a machine component are σ1 = 60MPa, σ2 = 5MPa and σ3 = -40 MPa. For the material of the component, the tensile
yield strength is σy = 200 MPa.
According to the maximum shear stress theory, the factor of
safety is
Answer : Option B
Explaination / Solution:
