Mechanical Engineering - Online Test

Q1. Two independent random variables X and Y are uniformly distributed in the interval [–1,1]. The probability that max[X, Y] is less than 1/2 is
Answer : Option B
Explaination / Solution:



Q2. Gear 2 rotates at 1200 rpm in counter clockwise direction and engages with Gear 3. Gear 3 and Gear 4 are mounted on the same shaft. Gear 5 engages with Gear 4. The numbers of teeth on Gears 2, 3, 4 and 5 are 20, 40, 15 and 30, respectively. The angular speed of Gear 5 is 

Answer : Option A
Explaination / Solution:



Q3. Which one of the following pairs of equations describes an irreversible heat engine?
Answer : Option A
Explaination / Solution:

For clausius theorem,  (for irreversible Heat engine).

Q4. Cutting tool is much harder than the workpiece. Yet the tool wears out during the tool-work interaction, because
Answer : Option C
Explaination / Solution:
No Explaination.


Q5. If , then the value of xx is
Answer : Option A
Explaination / Solution:



Q6. Consider the turbulent flow of a fluid through a circular pipe of diameter, D. Identify the correct pair of statements. 
I. The fluid is well-mixed 
II. The fluid is unmixed  
III. ReD < 2300 
IV. ReD > 2300  
Answer : Option D
Explaination / Solution:

ReD > 2300 means it is a turbulent flow. In turbulent flow, the fluid is well mixed. The fluid is unmixed, for a very-low Reynolds number laminar flow.  

Q7. The stress-strain curve for mild steel is shown in the figure given below. Choose the correct option referring to both figure and table.

Answer : Option C
Explaination / Solution:
No Explaination.


Q8. The hot tearing in a metal casting is due to
Answer : Option C
Explaination / Solution:
No Explaination.


Q9. With initial condition x(1) = 0.5, the solution of the differential equation  is
Answer : Option D
Explaination / Solution:



Q10. For a gas turbine power plant, identify the correct pair of statements. 
P. Smaller in size compared to steam power plant for same power output Starts quickly compared to steam power plant 
R. Works on the principle of Rankine cycle 
S. Good compatibility with solid fuel  
Answer : Option A
Explaination / Solution:

Steam power plants are bulky due to presence of boiler and condenser. Gas turbines are compact, as compressors and turbines are coupled on a common shaft. In steam power plants, boiler takes lot of time to get started, as compared to Gas Turbines.