BT-203 (GS) – Basic Mechanical Engineering

B.Tech. I & II Semester
Examination, November 2022
Grading System (GS)
Max Marks: 70 | Time: 3 Hours

Note:
i) Attempt any five questions.
ii) All questions carry equal marks.

Previous Year Questions (November 2022)

Q.1

a) Explain the methods to measure the hardness of materials.


b) A flat plate of area $1.5 \times 10^6 mm^2$ is pulled with a speed of 0.4 m/s relative to another plate located at a distance of 0.15 mm from it. Find the force and power required to maintain this speed, if the fluid separating them is having viscosity as 1 poise.[1 poise = 0.1 N s/m$^2$]

Answer (a): To be posted here.


Answer (b): To be posted here.

Q.2

a) Classify engineering materials. What do you mean by alloys? Write some applications of alloys.


b) A rod 200 cm long and of diameter 3.0 cm is subjected to an axial pull of 30 kN. If the Young's modulus of the material of the road is $2 \times 10^5$ N/mm$^2$, determine:

i) Stress

ii) Strain

iii) Elongation of the road

Answer (a): To be posted here.


Answer (b): To be posted here.

Q.3

a) With a neat diagram explain the main parts of a lathe machine. Explain any two operations performed on a lathe machine.


b) During a trial operation of a boiler 1630 kg of coal were consumed in 24 hrs. and 13000 kg of water evaporated. The mean steam pressure was 7 kgf/ cm$^2$ and condition dry saturated. The fuel contained 3 percent moisture and 4 percent ash and had a calorific value of 7200 kcal/kg. The feed water temperature was 35°C. Determine:

i) The boiler efficiency

ii) The equivalent evaporation per kg of dry coal

iii) The equivalent evaporation per kg of combustibles.

Answer (a): To be posted here.


Answer (b): To be posted here.

Q.4

a) Explain the working of a manometer for pressure measurement. Also relate absolute pressure, gauge pressure and vacuum pressure.


b) Explain the measurement process using vernier calliper with neat sketch.

Answer (a): To be posted here.


Answer (b): To be posted here.

Q.5

a) Define Viscosity. What is the importance of viscosity while selecting fluids in various engineering applications?


b) Discuss briefly the differences between externally fired and internally fired-steam generators. Also discuss the application of each type of steam generators.

Answer (a): To be posted here.


Answer (b): To be posted here.

Q.6

a) Explain working principle of hydraulic turbines (Pelton wheel) with neat sketch.


b) Derive an expression for efficiency of Otto cycle with neat sketches of PV and TS diagrams.

Answer (a): To be posted here.


Answer (b): To be posted here.

Q.7

a) State the Zeroth Law of thermodynamics. How is mercury in thermometer able to find the temperature of a body using the Zeroth law of thermodynamics?


b) Explain the working of four stroke diesel engine with neat sketch.

Answer (a): To be posted here.


Answer (b): To be posted here.

Q.8 Write Short notes on (Any two):

a) Welding defects

b) Dial gauge

c) Sine bar

d) Thermodynamic properties

Answer: To be posted here.