Mechanical Engineering - Online Test
Q1. Consider a slider crank mechanism with nonzero masses and inertia. A constant torque τ is applied on
the crank as shown in the figure. Which of the following plots best resembles variation of crank angle, θ versus time
Answer : Option B
Explaination / Solution:
No Explaination.
Q2. A box contains 4 white balls and 3 red balls. In succession, two balls are randomly selected and removed from the box. Given that the first removed ball is white, the probability that the second removed ball is red is
Answer : Option C
Explaination / Solution:
No Explaination.
Q3. For flow through a pipe of radius R, the velocity and temperature distribution are as follows:
where C1 and C2 are constants 
with Um being the mean velocity of flow. The value of Tm is
where C1 and C2 are constants with Um being the mean velocity of flow. The value of Tm is
Answer : Option C
Explaination / Solution:
Q4. In a DC arc welding operation, the voltage-arc length characteristic was obtained as Varc = 20 + 5l where the arc length l was varied between 5 mm and 7 mm. Here Varc denotes the arc voltage
in Volts. The arc current was varied from 400 A to 500 A. Assuming linear power source
characteristic, the open circuit voltage and the short circuit current for the welding operation are
Answer : Option C
Explaination / Solution:
No Explaination.
Q5. Among the four normal distributions
with probability density functions as
shown below, which one has the lowest
variance?
Answer : Option D
Explaination / Solution:
We have Probability distribution
function of Normal Distribution
σ also lowest
If σ decreases
f(x) increases (∵ from (1))
Curve will have highest peak
Q6. An Eigenvector of 
is
is
Answer : Option B
Explaination / Solution:
No Explaination.
Q7.
The speed of an engine varies from 210 rad/s to 190 rad/s. During the cycle the
change in kinetic energy is found to be 400 Nm. The inertia of the flywheel in
kg/m2 is
Answer : Option A
Explaination / Solution:
No Explaination.
Q8. In a single pass rolling process using 410 mm diameter steel rollers, a strip of width 140 mm and
thickness 8 mm undergoes 10% reduction of thickness. The angle of bite in radians is
Answer : Option C
Explaination / Solution:
No Explaination.
Q9. A machine element is subjected to the following bi-axial state of stress; σx = 80 MPa; σy = 20
MPa; τxy = 40MPa. If the shear strength of the material is 100 MPa, the factor of safety as
per Tresca‟s maximum shear stress theory is
Answer : Option B
Explaination / Solution:
Q10. For the differential equation 
with initial conditions x(0) = 1 and 
the solution is
with initial conditions x(0) = 1 and the solution is
Answer : Option B
Explaination / Solution:
No Explaination.
