Mechanical Engineering - Online Test
Q1. In a machining experiment, tool life was found to vary with the cutting speed in the following
manner:
The exponent (n) and constant (k) of the Taylor’s tool life equation are
Answer : Option A
Explaination / Solution:
No Explaination.
Q2. A cantilever beam of length L is subjected to a moment M at the free end. The moment of inertia
of the beam cross section about the neutral axis is l and the Young’s modulus is E. The magnitude
of the maximum deflection is
Answer : Option A
Explaination / Solution:
No Explaination.
Q3. Air enters an adiabatic nozzle at 300 kPa, 500 K with a velocity of 10 m/s. It leaves the nozzle at
100 kPa with a velocity of 180 m/s. The inlet area is 80 cm2. The specific heat of air Cp is 1008
J/kg.K.
The exit area of the nozzle in is
Answer : Option D
Explaination / Solution:
No Explaination.
Q4. If the semi-circular control D of radius 2 is as shown in the figure, then the
value of the integral 
is
is
Answer : Option A
Explaination / Solution:
Q5. A 5-point sequence x n is given as x - 3 = 1, x - = 1, x - 1 = , x = 5 and x 1 = 1. Let X(ei𝜔) denoted the discrete-time Fourier transform of x n.
The value of 
is
is
Answer : Option B
Explaination / Solution:
Q6. In a machining experiment, tool life was found to vary with the cutting speed in the following manner:
What is the percentage increase in tool life when the cutting speed is halved?
Answer : Option C
Explaination / Solution:
No Explaination.
Q7. A circular solid disc of uniform thickness 20 mm, radius 200 mm and mass 20 kg, is used as a
flywheel. If it rotates at 600 rpm, the kinetic energy of the flywheel, in Joules is
Answer : Option B
Explaination / Solution:
Q8. Specific enthalpy and velocity of steam at inlet and exit of a steam turbine,
running under steady state, are as given below:
Specific enthalpy (kJ/kg) Velocity(m/s)
Inlet steam condition 3250 180
Exit steam condition 2360 5
The rate of heat loss from the turbine per kg of steam flow rate is 5 kW.
Neglecting changes in potential energy of steam, the power developed in kW by
the steam turbine per kg of steam flow rate, is
Answer : Option C
Explaination / Solution:
Q9. An input to a 6-level quantizer has the probability density function f(x) as shown
in the figure. Decision boundaries of the quantizer are chosen so as to maximize the
entropy of the quantizer output. It is given that 3 consecutive decision boundaries
are' −1'. '0 ' and '1'.
The values of a and b are
Answer : Option A
Explaination / Solution:
Area under the pdf curve must be unity
2a + 4a + 4b = 1
2a + 8b = 1.................................................(1)
For maximum entropy three region must by equivaprobable thus
2a = 4b = 4b...............................................(2)
From (1) and (2) we get
b = 1/12 and a = 1/6
Q10. Mobility of a statically indeterminate structure is
Answer : Option A
Explaination / Solution:
No Explaination.
